Solution-based Post-processing and Electroless Nickel Plating Parameters Impacting the Microstructure and Hardness of Nickel-Plated L-shaped Additively Manufactured Steel Components.

Solution-based Post-processing and Electroless Nickel Plating Parameters Impacting the Microstructure and Hardness of Nickel-Plated L-shaped Additively Manufactured Steel Components. | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Solution-based Post-processing and Electroless Nickel Plating Parameters Impacting the Microstructure and Hardness of Nickel-Plated L-shaped Additively Manufactured Steel Components. Wondwosen Demisse, Pablo Sachez, Daniel Fulford, Lucas Rice, Kate L. Klein, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4372680/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 06 Aug, 2024 Read the published version in The International Journal of Advanced Manufacturing Technology → Version 1 posted 5 You are reading this latest preprint version Abstract Electroless coating brings the advantage of providing films on the complex geometry of additively manufactured components. However, there is a knowledge gap about the impact of AM part surface and postprocessing parameters on the quality of electroless coating. This study explores the application of three solution-based surface finishing techniques on the microstructure and surface hardness of additively manufactured stainless steel components coated with electroless nickel films. Given that AM techniques for metal parts often yield surfaces with inherently rough textures and differences in properties along the different planes, we investigated their relationship with nickel coating. To mitigate the impact of surface irregularities on electroless nickel coating quality, this research evaluated the effectiveness of chemical polishing (CP) and electropolishing (EP) as post-processing treatments for AM stainless steel. Characterization of the treated samples was conducted using the analytical Digital Microscope, Scanning Electron Microscope (SEM), and scratch tester. Additionally, the study incorporated an instant segmentation machine learning algorithm to overcome image analysis challenges. The findings indicate that EP and CP significantly improve surface smoothness, decreasing the arithmetical mean height (Ra) by as much as 4 µm and 10 µm, respectively. Furthermore, the nickel-coated AM samples demonstrated an enhancement in scratch resistance, exhibiting up to a two-fold increase in surface hardness compared to their as-built counterparts. Taguchi design of experiment was applied to investigate the effect of process parameters. This study provides insights for developing improved surface quality and acquiring new properties via the coating process to make AM parts suitable for challenging environments and novel applications. Additive manufacturing electroless nickel scratch test 3D printing Laser metal sintering Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 1. INTRODUCTION Additive manufacturing (AM) has brought a significant paradigm shift in the realm of product design and manufacturing [ 1 – 4 ]. While AM has substantially enhanced the efficiency of producing intricate metal components, however, as produced AM components remain susceptible to various issues, including wear [ 5 – 7 ], corrosion [ 8 – 11 ], fatigue [ 12 – 14 ], stress [ 15 – 17 ], and shear [ 18 – 21 ]. There is a pressing need for AM components to exhibit qualities such as high toughness, durability, and corrosion resistance. However, achieving the desired mechanical properties within a single material or production process presents a formidable challenge. Some materials may demonstrate exceptional corrosion resistance but simultaneously exhibit heightened susceptibility to mechanical stress, whereas others may possess remarkable deformation resistance but may prove unsuitable for utilization in acidic or saline environments [ 22 , 23 ]. It is widely recognized that the surface quality of a manufactured component has a direct bearing on factors such as wear, corrosion, and the initiation of cracks [ 24 ]. In cases where a component's surface finish is suboptimal, the likelihood of failure is considerably elevated [ 25 ]. Consequently, various post-processing techniques, including heat treatment, chemical treatment, spray coating, electroplating, and electroless plating, are extensively employed to ameliorate surface integrity and mitigate corrosion-related concerns [ 26 , 27 ]. It is a common observation that the as-produced surfaces of AM parts often fall short of the desired quality standards, necessitating post-processing interventions[ 28 – 30 ]. Electropolishing, also referred to as electrochemical polishing (Fig. 1 a), is a technique primarily used on metals such as stainless steel and aluminum for reducing the surface roughness [ 31 ]. The process involves submerging the metal component in an electrolyte solution, typically with an acidic composition. After that, an electrical current is applied, with the metal component acting as the anode. This initiates an electrochemical reaction that selectively eliminates a thin layer of material from the surface of the metal. As a result, numerous advantages are achieved [ 32 ]. Electropolishing effectively smooths the surface by eliminating scratches, imperfections, and microscopic peaks. It also excels in eliminating contaminants and embedded particles, thereby enhancing the cleanliness of the material. Furthermore, electropolishing contributes to improved corrosion resistance and significantly enhances surface brightness and reflectivity [ 33 ]. However, electropolishing is not possible for very intricate shapes involving difficult to access surface areas. For such a situation chempolishing can be adopted since it does not require typical counter electrode proximity to the target surface and electricity flow necessary in electropolishing (Fig. 1 a). Chempolishing (Fig. 1 b) is a chemical polishing technique that exhibits versatility in its application, catering to both metal and non-metal materials. This process entails immersing the component in a chemical bath specifically tailored for the material at hand [ 34 ]. The chemical solution selectively interacts with the surface, removing microscopic irregularities and asperities [ 35 ]. Chempolishing achieves surface uniformity and smoothness, making it highly effective in eliminating surface contaminants, oxides, and stains. It is a preferred method for enhancing the overall appearance of the material, offering an appealing and polished finish. Additionally, chempolishing can also contribute to improved corrosion resistance in certain cases [ 36 ]. Electroless plating offer excellent opportunities for bringing a wide range of new properties not available for the metal and alloys after additive manufacturing. Similar to chempolishing electroless plating can occur without requiring complex instrumentation and relatively unaffected by the AM part geometry. Electroless nickel plating is a very popular and successful method for improving surface wear resistance and corrosion protection. Electroless nickel plating (Fig. 1 c), a highly versatile and controlled process, plays a pivotal role in surface modification and engineering applications [ 37 ]. Unlike electroplating, it does not necessitate an external electrical current for metal deposition, rendering it a self-catalytic process. In this method, a carefully formulated aqueous solution, comprising a reducing agent and a source of nickel ions, is utilized to deposit a uniform layer of nickel onto the surface of a substrate, typically composed of metals like steel, aluminum, or copper [ 38 , 39 ]. The reduction reaction occurring on the substrate surface facilitates the controlled and precise deposition of nickel, leading to enhanced surface properties such as wear resistance, corrosion protection, and improved hardness. Electroless nickel plating finds wide-ranging utilization in industries encompassing aerospace, automotive, electronics, and engineering, owing to its ability to confer desirable material enhancements and precise coating thickness control [ 40 , 41 ]. In the present study, we have investigated three surface finishing methodologies to enhance the surface quality of additively manufactured surfaces (Fig. 1 ). Our investigation predominantly centers on the application of chemical-based techniques for reducing surface roughness in additively manufactured stainless steel specimens. The selection of chemical etching methodologies stems from their effectiveness in reducing surface roughness in concealed areas. We utilized electropolishing and chempolishing process for smoothing surfaces. Additionally, we expound upon our procedure for the generation of a protective coating on the chemically refined surfaces of the specimens. Our chosen approach involves the application of electroless nickel coatings to additively manufactured stainless steel samples. This paper provides a comprehensive exposition of the experimental procedures employed in obtaining EP, CP and electroless nickel coatings, accompanied by the application of machine learning instance segmentation for the analysis of microscopic and scanning electron microscopy (SEM) images. 2. METHODOLOGY 2.1 Sample Material The sample material chosen for this study is a molybdenum-alloyed austenitic steel, specifically Stainless Steel 316. Its composition primarily comprises iron, chromium, nickel, and molybdenum, with mass percentages typically falling within the range of 55–60% iron, 17–19% chromium, 13–15% nickel, 2–3% molybdenum, 6–8% carbon, along with trace amounts of other elements such as manganese and silicon (Fig. 2 ). The raw material powder, used in the experimentation, is spherical in shape and has a nominal particle size of 25 ± 15 µm. The production of stainless-steel powder is achieved through the atomization process, a well-established technique in powder metallurgy. Atomization entails the initial melting of the Stainless Steel 316 alloy, followed by subjecting it to high-pressure gas or water jets to disintegrate the molten metal into fine droplets. These droplets subsequently undergo rapid solidification, resulting in the formation of spherical particles during the cooling phase. 2.2 Sample Fabrication The specimens are fabricate using the EOS M280 laser sintering-based metal 3D printer, housed within the facilities of the Kansas City National Security Campus. The optimization of the 3D printing process for Stainless Steel 316L samples with the EOS M280 laser sintering-based metal 3D printer necessitates meticulous attention to crucial parameters. The process fine-tuning involves the establishment of a layer thickness of 40 microns, a laser power of 400 Watts, and a scanning speed of 7 m/s. Furthermore, the Powder Bed and Build Chamber Temperature maintain at 40 degrees Celsius ensures the creation of optimal sintering conditions. To prevent oxidation during the printing process and enhance the quality of the final product, a nitrogen gas atmosphere is employed. The implementation of these parameters guarantees the attainment of high-quality results in the 3D printing of stainless-steel specimens. 2.3 Sample Preparation The preparation of samples involves a series of sequential procedures designed to ensure the removal of various impurities and contaminants from the surface of the test specimens (Fig. 3 ) These contaminants typically encompass substances such as greases, oils, organic and inorganic compounds, tarnish, light rust, fingerprints, and oxides. Initially, the samples are subjected to a 3-minute sonication process in acetone, a solvent well-suited for dissolving greases, oils, resins, inks, permanent markers, adhesives, and paints. Subsequently, the samples undergo a thorough rinse with distilled water and are dried using a blower. Following this preliminary cleaning, the samples are subjected to a further 3-minute sonication step, utilizing 99% isopropyl alcohol (IPA), in an ultrasonic sonicator. This stage is instrumental in dissolving any remaining impurities on the sample surface. Following the IPA sonication, the next phases encompass intermediate-alkaline cleaning and electro-cleaning. Intermediate-alkaline cleaning is accomplished by immersing the samples in a sodium hypochlorite solution at 180°F for a brief duration of 2 minutes. This process serves to eliminate residual solvents and oils that may have been loosened during the initial pre-cleaning phase. Subsequent to intermediate-alkaline cleaning, the samples undergo a thorough rinse, drying, and electro-cleaning (EC). EC is an electrochemical process, utilizes an alkaline electrolyte and direct current (DC). In our experimental setup, a ready-to-use solution from Krohn Industrial Inc. was employed, maintaining the bath temperature at 180°F and applying a voltage of 10V for a duration of one and a half minutes. This electro-cleaning operation results in the formation of an oxide layer on the sample surface, necessitating a subsequent acid dip in HCL for 40 seconds to remove the oxide layer and neutralize the sample. Electropolishing method hinges on the use of highly concentrated acidic electrolytes, continually dissolving the sample throughout the electropolishing procedure. In electropolishing, the electrolyte comprises a mixture of 70% phosphoric acid and 30% sulfuric acid, with the preferred operational temperature sustained at 75°C. The sample is electrically connected to a power source along with the lead electrode, whereby the negative terminal is linked to the electrode (cathode), and the positive terminal is associated with the sample (anode). A current density of 70 A/dm2 is diligently applied over the course of 30 minutes during the electropolishing process. To neutralize the sample post-electropolishing, an alkaline solution is judiciously employed. To execute the chempolishing (CP) procedure, a highly concentrated acidic solution is employed as an electrolyte, serving the purpose of dissolving the areas of high-stress concentration and crack nucleation present on the submerged sample within the chemical bath. Notably, this process is electroless, with surface refinement occurring subsequent to the cleaning phase. The chemical bath, constituting a composition of 10–30% phosphoric acid, 1–10% hydrochloric acid, 1–10% nitric acid, and 1–10% proprietary surfactants, is a pivotal component of the chemo-polishing regimen. It is of paramount importance to rigorously maintain the bath temperature at a constant 75°C throughout the procedure, as deviations in temperature could lead to contamination of the chemical bath. Furthermore, agitation emerges as a critical element in the chemo-polishing protocol, effectively dispersing localized heat generated during the electropolishing phase. In the conducted experiments, agitation was meticulously executed through the utilization of a 20 mm magnetic stirrer set at 200 rpm. Following a 30-minute dissolution period, the samples were meticulously rinsed in distilled water. 2.4 Electroless Nickel Plating In the domain of electroless nickel plating, it is customary to employ three distinct types of solutions. The pivotal determinant in the deposition of nickel lies in the concentration of phosphorus within these solutions. In the scope of our specific investigation, we utilized electroless nickel plating solutions classified into three categories: low phosphorus (ONE PLATE 3001), mid phosphorus (ONE PLATE 1001), and high phosphorus (ONE PLATE 2001). These solutions were procured from Plating International Inc., recognized for their stability, characterized by pH values within the range of 5 to 6. It is imperative to ensure the pristine condition of the sample prior to commencing the deposition process, as any surface impurities may detrimentally affect the quality of deposition and impede the adhesion of the nickel coating. Therefore, meticulous cleansing of the substrate, free from any extraneous debris, oils, greases, or oxide layers, is a prerequisite. So, it is required that the sample pass through the standard cleaning process. Once this preparatory phase is concluded, the sample is ready to undergo activation. To guarantee optimal adhesion for subsequent plating, certain metals necessitate surface activation[ 42 , 43 ]. In our experiment, the sample underwent activation through immersion in a Woods nickel strike solution while being subjected to a direct current (DC) of 5V for a duration of 30 seconds. The plating procedure is conducted immediately subsequent to activation. The maintenance of an ideal temperature is of paramount importance during the electroless plating process, as any slight deviation in temperature could trigger an exothermic reaction with the potential to compromise the integrity of the samples. The recommended temperature for the bath solution in the case of low and medium phosphorus is 90°C, while for high phosphorus solutions, it is set at 85°C. The deposition time allocated for all samples was standardized at 30 minutes. Table 1 L9 Taguchi design of experiment (TDOE) DOE Phosphorus Content Surface Finish Orientation Temperature 1 High Elec-Polishing XY Plane T + 5 2 High Chem- Polishing YZ Plane T 3 High As-Built XZ Plane T − 5 4 Mid Elec- Polishing YZ Plane T − 5 5 Mid Chem- Polishing XZ Plane T + 5 6 Mid As-Built XY Plane T 7 Low Elec- Polishing XZ Plane T 8 Low Chem- Polishing XY Plane T − 5 9 Low As-Built YZ Plane T + 5 2.5 Taguchi Design of Experiment (TDOE) In the course of our experimental investigation, we employed a Taguchi Design of Experiments (TDOE) methodology, which encompasses a series of controlled experiments, characterized by four parameters, each exhibiting three distinct levels. The first parameter under scrutiny pertains to the concentration of phosphorus within the electroless nickel solution, with categorizations ranging from low, medium, to high levels. The second parameter centers around the type of surface finishing applied to ameliorate surface roughness, namely Electropolishing (EP), Chem-Polishing (CP), and the inherent as-built surfaces. The third parameter addresses the configuration of the 3D part coordinate plane, which significantly influences the surface characteristics resulting from the selective laser melting process. The core objective of our study lies in elucidating the responses of different plane surfaces to the deposition process. Finally, the fourth parameter revolves around the temperature of the nickel solution, which necessitates an optimal bath temperature tailored to each level. Our aim is to discern the manner in which the nickel solution reacts to temperature fluctuations relative to the established optimum temperature. To optimize the quality of experiments while concurrently streamlining the allocation of time and resources, we have adopted a strategic approach encompassing a temperature range spanning five degrees Celsius both below and above the defined optimum temperature. Through the judicious application of TDOE orthogonal arrays, we have effectively curtailed the number of requisite experiments to a total of nine trials. This methodological approach not only ensures the efficient utilization of resources and time but also provides in-depth understanding about the effect of different parameters and correlation among them. provides in-depth understanding about the effect of different parameters and correlation among them. 3. RESULTS AND DISCUSSION 3.1 Surface Roughness characterization after EP, CP, and as-built AM samples Surface characterization of the samples was conducted utilizing the KEYENCE Digital Microscope VHX-7000. Figure 5 summarizes different roughness parameters for the AM surface after three types of cleaning. Figure 4 a and 4 b, present the outcomes of the electropolishing surface finishing technique, revealing a substantially flatter topography with diminished hills and peaks. The associated surface roughness parameters are: Ra = 4.85 µm, Rz = 22.89 µm, RzJIS = 13.02 µm, Rp = 11.76 µm and Rv = 11.13 µm (Fig. 5 ). Figure 4 c and 4 d, illustrate the surface finish post chem-polishing. The corresponding surface roughness measurements are as follows: Ra = 11.65, Rz = 56.84 µm, RzJIS = 17.79 µm, Rp = 33.33 µm and Rv = 23.50 µm (Fig. 5 ). Figure 4 e-f, depict the surface topography of the as-built samples. The surface roughness parameters for the as-built specimens are as follows: Ra (arithmetic mean roughness) = 15.95 µm, Rz (the average maximum peak) = 86.99 µm, RzJIS (Ten-point mean roughness) = 38.54 µm, Rp (Maximum profile peak) = 40.73 µm,and Rv (Maximum profile valley depth) = 46.26 µm (Fig. 5 ). Figures 4 and 5 suggests that surface topography and roughness changed significantly after chempolishing and electropolishing. Figures 4 and 5 suggests that surface topography and roughness changed significantly after chempolishing and electropolishing. 3.2 Surface Roughness characterization after Nickel Plating To gain the insight about the role of surface treatment method and different coating parameters we investigated the 9 samples prepared as per the Taguchi Design of experiment scheme (Table 1 ). Figure 6 shows the topography of different DOE samples, whereas Fig. 7 summarizes the roughness data on each sample quantitatively. Figure 6 a in our study portrays the outcomes of Design of Experiment (DOE) #1, where a specific set of experimental parameters was employed (Table 1 ). These parameters encompassed the utilization of a high phosphorus nickel solution, an electropolished surface finish, orientation within the XY plane, and an elevated temperature exceeding the optimum by 5°C. (Fig. 7 )Fig. 6 b, denoting DOE#2, features a distinct combination of experimental parameters involving a high phosphorus nickel solution, chem-polished surface finish, alignment along the YZ plane, and an optimal temperature setting (Fig. 7 ). The resultant surface roughness measurements are as follows: Ra = 10.90 µm, Rz = 49.993 µm, RzJIS = 34.61 µm, Rp = 23.1 µm, Rv = 26.89 µm, Rc = 37.03 µm, Rt = 49.99 µm, and Rq = 12.90 µm (Fig. 7 ). In Fig. 6 c, we present the outcomes of DOE#3, executed with the utilization of a high phosphorus nickel solution, an as-built surface finish, alignment along the XZ plane, and a temperature setting lower than the optimum by 5°C. The measurements of surface roughness revealed the following values: Ra = 15.7639 µm, Rz = 70.21 µm, RzJIS = 19.22 µm, Rp = 35.01 µm, Rv = 35.20 µm, Rc = 35.63 µm, Rt = 70.23 µm, and Rq = 18.77µm. Figure 6 d, representing DOE#4, comprises parameters involving a mid-phosphorus nickel solution, an electropolished surface finish, alignment along the YZ plane, and a temperature set lower than the optimum by 5°C. The surface roughness characteristics of this configuration resulted in: Ra = 15.15 µm, Rz = 67.91 µm, RzJIS = 36.42 µm, Rp = 38.38 µm, Rv = 29.5267 µm, Rc = 43.58 µm, Rt = 67.94 µm, and Rq = 18.21 µm. Figure 6 e, representing DOE#5, encapsulates an experimental framework characterized by the use of a mid-phosphorus nickel solution, chemo-polished surface finish, alignment along the XZ plane, and an elevated temperature surpassing the optimum by 5°C. Surface roughness measurements for this setup yielded the following results: Ra = 14.59 µm, Rz = 73.4 µm, RzJIS = 36.18 µm, Rp = 32.95 µm, Rv = 40.45 µm, Rc = 44.43 µm, Rt = 73.4 µm, and Rq = 17.475 µm. Figure 6 f, representative of DOE#6, outlines a specific combination of parameters that incorporates a mid-phosphorus nickel solution, as-built surface finish, alignment along the XY plane, and the optimal temperature. The corresponding surface roughness measurements are as follows: Ra = 17.56 µm, Rz = 84.77 µm, RzJIS = 32.82 µm, Rp = 46.77 µm, Rv = 38.03 µm, Rc = 50.1 µm, Rt = 84.81 µm, and Rq = 21.0 µm (Fig. 7 ). Figure 6 g corresponds to DOE#7, characterized by the use of a low phosphorus nickel solution, an electropolished surface finish, alignment along the XZ plane, and the optimal temperature setting. Surface roughness measurements for this particular configuration revealed the following values: Ra = 18.54 µm, Rz = 87.49 µm, RzJIS = 17.44 µm, Rp = 46.06 µm, Rv = 41.42 µm, Rc = 25.57 µm, Rt = 87.54 µm, and Rq = 22.22 µm. Figure 6 h, emblematic of DOE#8, incorporates a set of parameters that entail a low phosphorus nickel solution, chemo-polished surface finish, alignment along the XY plane, and the temperature setting at the optimum level. The associated surface roughness characteristics are as follows: Ra = 17.44 µm, Rz = 71.88 µm, RzJIS = 20.65 µm, Rp = 32.87 µm, Rv = 39.01 µm, Rc = 55.84 µm, Rt = 71.9 µm, and Rq = 20.44 µm. Finally, Fig. 6 i represents DOE#9, wherein the experimental parameters encompass the utilization of a low phosphorus nickel solution, an as-built surface finish, alignment along the YZ plane, and a temperature exceeding the optimum by 5°C. The surface roughness measurements for this configuration resulted in the following values: Ra = 11.30 µm, Rz = 51.26 µm, RzJIS = 19.56 µm, Rp = 26.08 µm, Rv = 25.17 µm, Rc = 25.49 µm, Rt = 51.26 µm, and Rq = 13.66 µm (Fig. 7 ). 3.3 Scanning electron microscope (SEM) In high phosphorous solution (Figs. 8 a , 8 b, and 8 c) an approximate phosphorus concentration of up to 11% per deposition is observed. The primary objective of the coating is to maintain an amorphous structure, characterized by the absence of grain boundaries or phase boundaries, effectively mitigating the creation of initiation sites for corrosion. The mid phosphorous solution (Figs. 8 d , 8 e, and 8 f) provide evidence of robust adhesion and elevated plating hardness in the context of deposition on an as-built sample. Elemental analysis performed on the sample surface reveals an approximate phosphorus concentration of around 8% per deposition. Notably, the low phosphorous solution (Figs. 8 g , 8 h, and 8 i) in certain instances, observations indicate a phosphorus concentration of less than 5%, coupled with an inconsistent distribution pattern. 3.4 Scratch testing The utilization of scratch testing serves as a fundamental technique for the comprehensive analysis and characterization of mechanical wear behaviors. The meticulous application of precisely defined scratches, performed in a consistent and reproducible fashion, becomes of paramount importance in the pursuit of surface wear resistance characterization. In the scope of our study, we opted for the standard 10 N scratch test methodology, conducted on samples coated with nickel (Fig. 9 ). Each of the nine samples (Table 1 ) was subjected to scratch testing (Fig. 9 a-f). We were successful in obtaining clear scratch on nickel coated sample with high phosphorous content (Fig. 9 a-c), medium phosphorous content (Fig. 9 d-f), and low phosphorous content (Fig. 9 g-i). However, a major challenge was in analyzing different scratches. The acquisition of precise measurements of the scratch width from the microscopic imagery was difficult due to the scratch's inconsistent width. Consequently, the methodology has been adapted to calculate the projected area of the scratch, which is then divided by its length to achieve a standardized measure (Fig. 10 a). In the realm of image segmentation, the Segment Anything Model (SAM), developed by Meta, previously known as Facebook, has been employed. As a foundational model for segmentation, SAM has undergone training on a dataset encompassing 11 million images and in excess of one billion masks. The architecture of SAM is tripartite, consisting of an image encoder, a prompt encoder, and a mask decoder. The strength of SAM lies in its dual utility, offering both a no-code and a code-based solution. For the purposes of our experiment, the no-code, fully online option was selected. Subsequent to this, we applied denoising and thresholding processes using ImageJ to refine the results (example shown in, Fig. 10 b). Once we have performed instance segmentation and thresholding on the scratch, we proceed to determine the material's level of hardness using a formula. $$Hs = 8P/\varPi {w}^{2}$$ Where, Hs = Scratch hardness number (MPa) P = Normal force (N) w = scratch width Upon a meticulous analysis of the results derived from the 10 N scratch test, a conspicuous enhancement in scratch resistance was observed both prior to and subsequent to the test. As depicted in Fig. 9 , it is discernible that Design of Experiment (DOE) #2 and #7 exhibited a substantial augmentation in scratch resistance, reaching an impressive increase of up to 50%. Furthermore, DOE #4, #5, #8, and #9 displayed a marked improvement in surface hardness, manifesting enhancements that ranged from 51–86%. Of notable significance, DOE #6 exhibited the most substantial advancement in surface hardness, registering an impressive escalation of 128%. However, it is worth mentioning that the remaining experiments failed to yield any substantial improvements in surface hardness. Hardness data before and after nickel coating has been summarized in Fig. 11 . Table 2 Surface Hardness before and after Ni coating DOE Hardness before Ni deposition Hardness after Ni deposition 1 125.13 332.64 2 119.67 338.10 3 207.47 587.53 4 218.19 610.02 5 194.94 538.22 6 297.36 890.48 7 219.64 643.89 8 233.46 660.62 9 269.18 815.58 3.5 Taguchi Analisis Multi-plots serve as a visualization tool for elucidating the impacts of numerous factors on a response variable (Fig. 12 ). Within these plots, the presentation encompasses both main effects and interaction effects of the factors on the response variable (Fig. 12 ). The main effects delineate the individual influence of each factor on the response variable, while the interaction effects depict the collective impact of two or more factors on the response variable. Phosphorous level impacted significantly (Fig. 12 a); high Phosphorous conetent appear to yield low hardness as compared to the medium and low phosphorous content. Interestingly, electropolish and chempolish surface treatment yielded similar effect (Fig. 12 b). The unpolished surface behaved very differently (Fig. 12 a). The surface orientation and temperature factor’s level impact was relatively weaker (Fig. 1 c,d). Different sample orientation produced different impact (Fig. 12 c); XY orientation behaved significantly different than that of XZ and YZ orientation (Fig. 12 c). Temperature effect was similar for level T and T + 5, and it was different as compared to T-5 (Fig. 12 d). We also studied the strength of interaction between two parameters. All potential interactions between pairs of two factors are computed (Fig. 13 .a). The interaction pairs are presented in a descending order based on their Severity Index (SI), which is expressed on a scale from 0 to 100%. In cases involving interactions among pairs of factors with 3 levels, the Severity Index (SI) is indicative of the highest angle within the array of feasible combinations of line segments (Fig. 13 .a). Interaction data shows relative independence of a factor in relation to other factor. The highest interaction strength of 92.78 was observered between the orientation and temperature; it means changing orientation will necessiate adjustment in the plating temperature for the desired results (Fig. 13 a). On the other hand, low severity index of 6.92 phosphorous and surface finish interaction shows their independence from each other. We also investigated the impact of individual factor on film hardness (Fig. 13 b). Phosphorus content is main factor in deciding the nickel coating hardness (Fig. 13 b). This result is in line with the prior literature relating the phosphorous content to the hardness of the nickel coating (Fig. 13 b). Interestingly, surface finishing method was the second most important factor (Fig. 13 b). This result is of critical importance in the light of the degree of complexity involved in AM geometry. Hardness is highest for the As built surface. The reason is that high roughness enable creating better grip of the coating material on the surface (Fig. 13 b), this result is consistent with the prior literature defining the impact of roughness on the film adhesion. We also employed Taguchi Design of experiment analysis to investigate the combination of parameters that will lead to the highest hardness. The optimal table represent the predictive equation delineating the anticipated performance under optimal conditions as well as any conceivable alternative conditions. The numerical values presented in the table are derived from computations conducted under the optimal condition, a state determined by the chosen quality characteristic for analysis. Conventional practice dictates the inclusion of only statistically significant factors (without pooling) in the computation of anticipated performance, aligning with established analytical methodologies. In the context of this experiment, The optimal condition for achieving the highest hardness is identified as a low-phosphorus nickel solution, coupled with a as-built surface finish, XY orientation, and a solution temperature of 90 degrees Celsius. 4. CONCLUSION This study explores the utilization of electropolishing (EP) and chempolishing (CP) techniques for the removal of surface roughness, coupled with the subsequent application of electroless nickel plating as a protective layer coating on stainless-steel samples fabricated through additive manufacturing. These findings encapsulate the principal outcomes of the investigation. The process of electropolishing exhibits a notable capability for achieving high-quality surface finishing, characterized by the rapid removal of material. Nevertheless, it is essential to acknowledge that this method is not without its limitations, particularly in terms of achieving uniformity and consistency across surfaces. In contrast, chempolishing emerges as a compelling alternative, primarily due to its capacity to uniformly remove material and impart smoothness to both internal and external surfaces. Electroless nickel deposition, as a plating technique, proves to be a highly suitable choice for enhancing the properties of stainless-steel samples generated through additive manufacturing. Nickel, with its inherent attributes, offers superior wear resistance, as corroborated by scratch testing, which has demonstrated that nickel-plated samples exhibit up to twice the resistance compared to their non-plated counterparts. Furthermore, the utilization of a high-phosphorus electroless nickel solution presents an additional advantage in terms of augmenting corrosion resistance. It is pertinent to emphasize that the geometrical characteristics of the printed component play a pivotal role in influencing the surface finishing process. To attain a lustrous and impeccably smooth surface characterized by exceptional hardness and corrosion resistance, it may become imperative to employ a sequence of successive surface finishing techniques. In conclusion, it has been observed that the optimal combination yielding the highest surface hardness involves the utilization of a low-phosphorus nickel solution, along with a built surface finish, XY orientation, and a solution temperature of 90 degrees Celsius Declarations Competing Interests Financial interests: Authors declare they have no financial interests Funding This research was funded by National Science Foundation-CREST Award, grant number HRD- 1914751, Department of Energy/ National Nuclear Security Agency (DE-FOA-0003945), the Department of Energy’s Kansas City National Security Campus. The Department of Energy’s Kansas City National Security Campus is operated and managed by Honeywell Federal Manufacturing & Technologies, LLC under contract number DE-NA0002839 and The NASA MUREP Institutional Research Opportunity Grant under Cooperative Agreement #80NSSC19M0196. Author contributions The inception of the research idea was attributed to Pawan Tyagi. Experimental procedures were executed by Wondwosen, Dan, and Pablo. Subsequently, the composition of the manuscript fell under the responsibility of Wondwosen, with subsequent critical evaluation undertaken by both Pawan Tyagi and Kate Klein. Pawan Tyagi contributed experimental data pertinent to chemo-polishing and electropolishing procedures. Additionally, the provision of experimental samples was facilitated by Lucas Rice. Data Availability: Data used in this paper will be made available upon reasonable request. 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J Manuf Process 29:149–159 Melia MA, Nguyen H-DA, Rodelas JM, Schindelholz EJ (2019) Corrosion properties of 304L stainless steel made by directed energy deposition additive manufacturing. Corros Sci 152:20–30 Örnek C (2018) Additive manufacturing–a general corrosion perspective. Corros Eng Sci Technol 53(7):531–535 Ko G, Kim W, Kwon K, Lee T-K (2021) The corrosion of stainless steel made by additive manufacturing: A review, Metals , vol. 11, no. 3, p. 516 Revilla RI et al (2020) Microstructure and corrosion behavior of 316L stainless steel prepared using different additive manufacturing methods: A comparative study bringing insights into the impact of microstructure on their passivity. Corros Sci 176:108914 Huynh L, Rotella J, Sangid MD (2016) Fatigue behavior of IN718 microtrusses produced via additive manufacturing. Mater Design 105:278–289 Gockel J, Sheridan L, Koerper B, Whip B (2019) The influence of additive manufacturing processing parameters on surface roughness and fatigue life. Int J Fatigue 124:380–388 Yadollahi A, Shamsaei N (2017) Additive manufacturing of fatigue resistant materials: Challenges and opportunities. Int J Fatigue 98:14–31 Carpenter K, Tabei A (2020) On residual stress development, prevention, and compensation in metal additive manufacturing, Materials , vol. 13, no. 2, p. 255 Szost BA et al (2016) A comparative study of additive manufacturing techniques: Residual stress and microstructural analysis of CLAD and WAAM printed Ti–6Al–4V components. Mater Design 89:559–567 Li C, Liu Z, Fang X, Guo Y (2018) Residual stress in metal additive manufacturing. Procedia Cirp 71:348–353 James S, Dang C (2020) Investigation of shear failure load in ultrasonic additive manufacturing of 3D CFRP/Ti structures. J Manuf Process 56:1317–1321 Hehr A, Dapino MJ (2015) Interfacial shear strength estimates of NiTi–Al matrix composites fabricated via ultrasonic additive manufacturing. Compos Part B: Eng 77:199–208 Yavas D, Zhang Z, Liu Q, Wu D (2021) Interlaminar shear behavior of continuous and short carbon fiber reinforced polymer composites fabricated by additive manufacturing. Compos Part B: Eng 204:108460 Chen J et al (2021) Adiabatic shear band development and following failure in 316L fabricated by an additive manufacturing process. Mater Sci Engineering: A 811:141003 Biserova-Tahchieva A, Biezma-Moraleda MV, Llorca-Isern N, Gonzalez-Lavin J, Linhardt P (2023) Additive Manufacturing Processes in Selected Corrosion Resistant Materials: A State of Knowledge Review, Materials , vol. 16, no. 5, p. 1893 Megahed M, Mindt H-W, N’Dri N, Duan H, Desmaison O (2016) Metal additive-manufacturing process and residual stress modeling. Integrating Mater Manuf Innov 5:61–93 Croll S (2020) Surface roughness profile and its effect on coating adhesion and corrosion protection: A review. Prog Org Coat 148:105847 Tyagi P et al (2019) Reducing the roughness of internal surface of an additive manufacturing produced 316 steel component by chempolishing and electropolishing. Additive Manuf 25:32–38 Technology K (2021) 8 Metal Surface Finishing Treatment Processes. https://www.kellertechnology.com/blog/8-common-types-of-surface-treatments-for-metal-parts/ (accessed Jun 29 Metal Finishing–What Types of Finishes Are There (2021) https://www.thomasnet.com/articles/custom-manufacturing-fabricating/types-metal-finishing / (accessed Jun 29 Kumbhar NN, Mulay A (2018) Post processing methods used to improve surface finish of products which are manufactured by additive manufacturing technologies: a review. J Institution Eng (India): Ser C 99:481–487 Peng X, Kong L, Fuh JYH, Wang H (2021) A review of post-processing technologies in additive manufacturing. J Manuf Mater Process 5(2):38 Mahmood MA, Chioibasu D, Ur Rehman A, Mihai S, Popescu AC (2022) Post-processing techniques to enhance the quality of metallic parts produced by additive manufacturing, Metals , vol. 12, no. 1, p. 77 Yang G, Wang B, Tawfiq K, Wei H, Zhou S, Chen G (2017) Electropolishing of surfaces: theory and applications. Surf Eng 33(2):149–166 Landolt D (1987) Fundamental aspects of electropolishing. Electrochim Acta 32(1):1–11 Ziemniak SE, Hanson M, Sander PC (2008) Electropolishing effects on corrosion behavior of 304 stainless steel in high temperature, hydrogenated water. Corros Sci 50(9):2465–2477 Demisse W, Mutunga E, Klein K, Rice L, Tyagi P (2021) Surface finishing and electroless nickel plating of additively manufactured (am) metal components, in ASME International Mechanical Engineering Congress and Exposition , vol. 85550: American Society of Mechanical Engineers, p. V02AT02A038 Dillard J, Grizzle A, Demisse W, Rice L, Klein K, Tyagi P (2022) Alternating chempolishing and electropolishing for interior and exterior surface finishing of additively manufactured (AM) metal components. Int J Adv Manuf Technol 121:11–12 Bedmar J, Abu-Warda N, García-Rodríguez S, Torres B, Rams J (2022) Influence of the surface state on the corrosion behavior of the 316 L stainless steel manufactured by laser powder bed fusion. Corros Sci 207:110550 Loto C (2016) Electroless nickel plating–a review. Springer Delaunois F, Vitry V, Bonin L (2019) Electroless nickel plating: fundamentals to applications. CRC Sudagar J, Lian J, Sha W (2013) Electroless nickel, alloy, composite and nano coatings–A critical review. J Alloys Compd 571:183–204 Mallory GO, Hajdu JB (1990) Electroless plating: fundamentals and applications. William Andrew Hajdu J, Zabrocky S (2000) The future of electroless nickel. Met Finish 98(5):42–46 Wang L, Li J, Liu H (2011) A simple process for electroless plating nickel–phosphorus film on wood veneer. Wood Sci Technol 45:161–167 Kiguchi M (2017) Surface modification and activation of wood. Chemical modification of lignocellulosic materials. Routledge, pp 197–227 Cite Share Download PDF Status: Published Journal Publication published 06 Aug, 2024 Read the published version in The International Journal of Advanced Manufacturing Technology → Version 1 posted Editorial decision: Major Revisions Needed 17 Jul, 2024 Reviewers agreed at journal 27 May, 2024 Reviewers invited by journal 07 May, 2024 Editor assigned by journal 06 May, 2024 First submitted to journal 05 May, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4372680","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":299793796,"identity":"6c0c6df6-6efd-4c78-97d1-2350e46f2024","order_by":0,"name":"Wondwosen Demisse","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Wondwosen","middleName":"","lastName":"Demisse","suffix":""},{"id":299793797,"identity":"734c02b2-de75-4eae-b86e-b92c1d221049","order_by":1,"name":"Pablo Sachez","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Pablo","middleName":"","lastName":"Sachez","suffix":""},{"id":299793798,"identity":"71f3aac5-b270-45ec-9af3-299276ada5e0","order_by":2,"name":"Daniel Fulford","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Daniel","middleName":"","lastName":"Fulford","suffix":""},{"id":299793799,"identity":"94a81cf6-16cd-4eef-a229-afb2689f8454","order_by":3,"name":"Lucas Rice","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Lucas","middleName":"","lastName":"Rice","suffix":""},{"id":299793800,"identity":"925f5fe4-f6a3-468d-8edd-dcd9ef551985","order_by":4,"name":"Kate L. Klein","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Kate","middleName":"L.","lastName":"Klein","suffix":""},{"id":299793801,"identity":"3cc7af75-a927-4af8-9894-6e95de1ac839","order_by":5,"name":"Pawan Tyagi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAs0lEQVRIiWNgGAWjYNACAxsGhgNAmoco1WxgLWkka2E4TIIWc/kew49fCs4n9h0/wPjgbRsRWizbeIylZQxuJ848k8BsOJcYLQbHeAykJYBaNtxgYJPmJVKL8W8Jg3MgLey/idViJvnB4ADYFmaitFi2pZVZMxgkG888k9gsOeccEVrMmQ9vvvnjj51s3/HDBz+8KSPGYQwcBsyQ6GBsIEI9WAv7A8YfxKkdBaNgFIyCkQoAotY37mkWYM0AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-7541-1344","institution":"University of the District of Columbia","correspondingAuthor":true,"prefix":"","firstName":"Pawan","middleName":"","lastName":"Tyagi","suffix":""}],"badges":[],"createdAt":"2024-05-05 17:41:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4372680/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4372680/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00170-024-14217-z","type":"published","date":"2024-08-06T15:57:06+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":56564175,"identity":"992ec549-9ec7-49c9-b0fc-19373a9fc8d1","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":48303,"visible":true,"origin":"","legend":"\u003cp\u003eSchematics of experimental set up for (a) Electropolishing, (b) Chempolishing, and (c) electroless nickel plating of any sample.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/2907b772cfdd1033bb8298f8.png"},{"id":56564184,"identity":"5caca52f-24b2-49cb-953f-2cca1c3d05fb","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":320328,"visible":true,"origin":"","legend":"\u003cp\u003eL-shaped stainless steel AM samples.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/7dd8b99b0beca42ff5256c6c.png"},{"id":56564177,"identity":"ecadd31f-fb96-4f4d-9855-60fdf1db9a79","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":17686,"visible":true,"origin":"","legend":"\u003cp\u003eStandard cleaning process steps\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/1f442db387a6454468319362.png"},{"id":56564179,"identity":"a9c95ce9-95b9-4fe2-be2d-0a31aa46ff81","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":848125,"visible":true,"origin":"","legend":"\u003cp\u003eMicroscopic imagery for (a) Top view - electropolishing, (b) Isometric view - electropolishing, (c) Top view - chempolishing, (d) Isometric view - chempolishing, (e) Top view – As built, (f) Isometric view - As built.\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/6ed5d083a49a58d71cbd08f8.jpg"},{"id":56564630,"identity":"2e35d1da-e8b7-481d-b0d3-024a7101688b","added_by":"auto","created_at":"2024-05-15 22:50:43","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":32793,"visible":true,"origin":"","legend":"\u003cp\u003eBar chart for different topographical parameters after three surface finishing methods.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/894f5bc5829af1aa84c7e917.png"},{"id":56564631,"identity":"93ca048f-0611-43f4-b9f2-ead053977cca","added_by":"auto","created_at":"2024-05-15 22:50:43","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":876347,"visible":true,"origin":"","legend":"\u003cp\u003eMicroscopy imagery for (a) DOE#1, (b) DOE#2, (c) DOE#3, (d) DOE#4, (e) DOE#5, (f) DOE#6, (g) DOE#7, (h) DOE#7, (i) DOE#8, (j) DOE#9\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/b7a9abdb091b5aac74982f25.jpg"},{"id":56564629,"identity":"0ab8aa14-7ba6-4935-b424-a46ecc2b23b7","added_by":"auto","created_at":"2024-05-15 22:50:43","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":29572,"visible":true,"origin":"","legend":"\u003cp\u003eBar chart representing the roughness for the nine experiments after nickel deposition.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/c79338855bc9fa3f54d3dfaf.png"},{"id":56564181,"identity":"4570fbf3-db94-41cd-9a34-146600683c8e","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":973348,"visible":true,"origin":"","legend":"\u003cp\u003eSEM imagery for (a) DOE#1, (b) DOE#2, (c) DOE#3, (d) DOE#4, (e) DOE#5, (f) DOE#6, (g) DOE#7, (h) DOE#7, (i) DOE#8, (j) DOE#9\u003c/p\u003e","description":"","filename":"8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/8030e13c65c1a0d52970dc7d.jpg"},{"id":56564187,"identity":"89a9a173-7cc3-46bf-ab0b-d0c3044b3dd2","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":721360,"visible":true,"origin":"","legend":"\u003cp\u003eScratch microscopy imagery for (a) DOE#1, (b) DOE#2, (c) DOE#3, (d) DOE#4, (e) DOE#5, (f) DOE#6, (g) DOE#7, (h) DOE#7, (i) DOE#8, (j) DOE#9\u003c/p\u003e","description":"","filename":"9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/934daa263d5e74b54e10e995.jpg"},{"id":56564632,"identity":"dfad372d-21a8-4db9-9f66-f0ac0f10afb9","added_by":"auto","created_at":"2024-05-15 22:50:43","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":408032,"visible":true,"origin":"","legend":"\u003cp\u003e(a) scratch image from SAM model (b) image after denoise and threshold\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/4920e6675c575b4b1d098015.png"},{"id":56564182,"identity":"b7a9ff8c-88d6-4079-96dd-f23d3c7e9b4e","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":37639,"visible":true,"origin":"","legend":"\u003cp\u003eBar chart representing the roughness for the nine experiments after nickel deposition\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/e2902cbc5077f952ecc24845.png"},{"id":56564186,"identity":"e0e80859-b12c-4ece-9d1e-9b809273cd2e","added_by":"auto","created_at":"2024-05-15 22:42:43","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":65499,"visible":true,"origin":"","legend":"\u003cp\u003eTachuchi Multi-plot analisys (a) phosphous (b) surface finish (c) Orientation (d) Temprature\u003c/p\u003e","description":"","filename":"12.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/cb6c28038ccbd874a70ee4ce.png"},{"id":56564633,"identity":"b882185d-7a29-4ede-aea3-220bf70998c0","added_by":"auto","created_at":"2024-05-15 22:50:43","extension":"png","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":46388,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Interaction among factors \u0026nbsp;(b) ANOVA analysis of Impact of individual factors.\u003c/p\u003e","description":"","filename":"13.png","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/c4b474efb616861c6bda74ab.png"},{"id":62298716,"identity":"7d4ff7d7-228a-4df0-9300-9f113208801b","added_by":"auto","created_at":"2024-08-12 16:16:13","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4929099,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4372680/v1/c6f42734-7ff2-43a7-a573-fb567ba4e726.pdf"}],"financialInterests":"","formattedTitle":"Solution-based Post-processing and Electroless Nickel Plating Parameters Impacting the Microstructure and Hardness of Nickel-Plated L-shaped Additively Manufactured Steel Components.","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eAdditive manufacturing (AM) has brought a significant paradigm shift in the realm of product design and manufacturing [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. While AM has substantially enhanced the efficiency of producing intricate metal components, however, as produced AM components remain susceptible to various issues, including wear [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], corrosion [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], fatigue [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], stress [\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], and shear [\u003cspan additionalcitationids=\"CR19 CR20\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. There is a pressing need for AM components to exhibit qualities such as high toughness, durability, and corrosion resistance. However, achieving the desired mechanical properties within a single material or production process presents a formidable challenge. Some materials may demonstrate exceptional corrosion resistance but simultaneously exhibit heightened susceptibility to mechanical stress, whereas others may possess remarkable deformation resistance but may prove unsuitable for utilization in acidic or saline environments [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. It is widely recognized that the surface quality of a manufactured component has a direct bearing on factors such as wear, corrosion, and the initiation of cracks [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In cases where a component's surface finish is suboptimal, the likelihood of failure is considerably elevated [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Consequently, various post-processing techniques, including heat treatment, chemical treatment, spray coating, electroplating, and electroless plating, are extensively employed to ameliorate surface integrity and mitigate corrosion-related concerns [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. It is a common observation that the as-produced surfaces of AM parts often fall short of the desired quality standards, necessitating post-processing interventions[\u003cspan additionalcitationids=\"CR29\" citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eElectropolishing, also referred to as electrochemical polishing (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea), is a technique primarily used on metals such as stainless steel and aluminum for reducing the surface roughness [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. The process involves submerging the metal component in an electrolyte solution, typically with an acidic composition. After that, an electrical current is applied, with the metal component acting as the anode. This initiates an electrochemical reaction that selectively eliminates a thin layer of material from the surface of the metal. As a result, numerous advantages are achieved [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Electropolishing effectively smooths the surface by eliminating scratches, imperfections, and microscopic peaks. It also excels in eliminating contaminants and embedded particles, thereby enhancing the cleanliness of the material. Furthermore, electropolishing contributes to improved corrosion resistance and significantly enhances surface brightness and reflectivity [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. However, electropolishing is not possible for very intricate shapes involving difficult to access surface areas. For such a situation chempolishing can be adopted since it does not require typical counter electrode proximity to the target surface and electricity flow necessary in electropolishing (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea).\u003c/p\u003e \u003cp\u003eChempolishing (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb) is a chemical polishing technique that exhibits versatility in its application, catering to both metal and non-metal materials. This process entails immersing the component in a chemical bath specifically tailored for the material at hand [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The chemical solution selectively interacts with the surface, removing microscopic irregularities and asperities [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Chempolishing achieves surface uniformity and smoothness, making it highly effective in eliminating surface contaminants, oxides, and stains. It is a preferred method for enhancing the overall appearance of the material, offering an appealing and polished finish. Additionally, chempolishing can also contribute to improved corrosion resistance in certain cases [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eElectroless plating offer excellent opportunities for bringing a wide range of new properties not available for the metal and alloys after additive manufacturing. Similar to chempolishing electroless plating can occur without requiring complex instrumentation and relatively unaffected by the AM part geometry. Electroless nickel plating is a very popular and successful method for improving surface wear resistance and corrosion protection. Electroless nickel plating (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec), a highly versatile and controlled process, plays a pivotal role in surface modification and engineering applications [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. Unlike electroplating, it does not necessitate an external electrical current for metal deposition, rendering it a self-catalytic process. In this method, a carefully formulated aqueous solution, comprising a reducing agent and a source of nickel ions, is utilized to deposit a uniform layer of nickel onto the surface of a substrate, typically composed of metals like steel, aluminum, or copper [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. The reduction reaction occurring on the substrate surface facilitates the controlled and precise deposition of nickel, leading to enhanced surface properties such as wear resistance, corrosion protection, and improved hardness. Electroless nickel plating finds wide-ranging utilization in industries encompassing aerospace, automotive, electronics, and engineering, owing to its ability to confer desirable material enhancements and precise coating thickness control [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the present study, we have investigated three surface finishing methodologies to enhance the surface quality of additively manufactured surfaces (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Our investigation predominantly centers on the application of chemical-based techniques for reducing surface roughness in additively manufactured stainless steel specimens. The selection of chemical etching methodologies stems from their effectiveness in reducing surface roughness in concealed areas. We utilized electropolishing and chempolishing process for smoothing surfaces. Additionally, we expound upon our procedure for the generation of a protective coating on the chemically refined surfaces of the specimens. Our chosen approach involves the application of electroless nickel coatings to additively manufactured stainless steel samples. This paper provides a comprehensive exposition of the experimental procedures employed in obtaining EP, CP and electroless nickel coatings, accompanied by the application of machine learning instance segmentation for the analysis of microscopic and scanning electron microscopy (SEM) images.\u003c/p\u003e"},{"header":"2. METHODOLOGY","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Sample Material\u003c/h2\u003e \u003cp\u003eThe sample material chosen for this study is a molybdenum-alloyed austenitic steel, specifically Stainless Steel 316. Its composition primarily comprises iron, chromium, nickel, and molybdenum, with mass percentages typically falling within the range of 55\u0026ndash;60% iron, 17\u0026ndash;19% chromium, 13\u0026ndash;15% nickel, 2\u0026ndash;3% molybdenum, 6\u0026ndash;8% carbon, along with trace amounts of other elements such as manganese and silicon (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The raw material powder, used in the experimentation, is spherical in shape and has a nominal particle size of 25\u0026thinsp;\u0026plusmn;\u0026thinsp;15 \u0026micro;m. The production of stainless-steel powder is achieved through the atomization process, a well-established technique in powder metallurgy. Atomization entails the initial melting of the Stainless Steel 316 alloy, followed by subjecting it to high-pressure gas or water jets to disintegrate the molten metal into fine droplets. These droplets subsequently undergo rapid solidification, resulting in the formation of spherical particles during the cooling phase.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Sample Fabrication\u003c/h2\u003e \u003cp\u003eThe specimens are fabricate using the EOS M280 laser sintering-based metal 3D printer, housed within the facilities of the Kansas City National Security Campus. The optimization of the 3D printing process for Stainless Steel 316L samples with the EOS M280 laser sintering-based metal 3D printer necessitates meticulous attention to crucial parameters. The process fine-tuning involves the establishment of a layer thickness of 40 microns, a laser power of 400 Watts, and a scanning speed of 7 m/s. Furthermore, the Powder Bed and Build Chamber Temperature maintain at 40 degrees Celsius ensures the creation of optimal sintering conditions. To prevent oxidation during the printing process and enhance the quality of the final product, a nitrogen gas atmosphere is employed. The implementation of these parameters guarantees the attainment of high-quality results in the 3D printing of stainless-steel specimens.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Sample Preparation\u003c/h2\u003e \u003cp\u003eThe preparation of samples involves a series of sequential procedures designed to ensure the removal of various impurities and contaminants from the surface of the test specimens (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) These contaminants typically encompass substances such as greases, oils, organic and inorganic compounds, tarnish, light rust, fingerprints, and oxides. Initially, the samples are subjected to a 3-minute sonication process in acetone, a solvent well-suited for dissolving greases, oils, resins, inks, permanent markers, adhesives, and paints. Subsequently, the samples undergo a thorough rinse with distilled water and are dried using a blower. Following this preliminary cleaning, the samples are subjected to a further 3-minute sonication step, utilizing 99% isopropyl alcohol (IPA), in an ultrasonic sonicator. This stage is instrumental in dissolving any remaining impurities on the sample surface.\u003c/p\u003e \u003cp\u003eFollowing the IPA sonication, the next phases encompass intermediate-alkaline cleaning and electro-cleaning. Intermediate-alkaline cleaning is accomplished by immersing the samples in a sodium hypochlorite solution at 180\u0026deg;F for a brief duration of 2 minutes. This process serves to eliminate residual solvents and oils that may have been loosened during the initial pre-cleaning phase.\u003c/p\u003e \u003cp\u003eSubsequent to intermediate-alkaline cleaning, the samples undergo a thorough rinse, drying, and electro-cleaning (EC). EC is an electrochemical process, utilizes an alkaline electrolyte and direct current (DC). In our experimental setup, a ready-to-use solution from Krohn Industrial Inc. was employed, maintaining the bath temperature at 180\u0026deg;F and applying a voltage of 10V for a duration of one and a half minutes. This electro-cleaning operation results in the formation of an oxide layer on the sample surface, necessitating a subsequent acid dip in HCL for 40 seconds to remove the oxide layer and neutralize the sample.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eElectropolishing method hinges on the use of highly concentrated acidic electrolytes, continually dissolving the sample throughout the electropolishing procedure. In electropolishing, the electrolyte comprises a mixture of 70% phosphoric acid and 30% sulfuric acid, with the preferred operational temperature sustained at 75\u0026deg;C. The sample is electrically connected to a power source along with the lead electrode, whereby the negative terminal is linked to the electrode (cathode), and the positive terminal is associated with the sample (anode). A current density of 70 A/dm2 is diligently applied over the course of 30 minutes during the electropolishing process. To neutralize the sample post-electropolishing, an alkaline solution is judiciously employed. To execute the chempolishing (CP) procedure, a highly concentrated acidic solution is employed as an electrolyte, serving the purpose of dissolving the areas of high-stress concentration and crack nucleation present on the submerged sample within the chemical bath. Notably, this process is electroless, with surface refinement occurring subsequent to the cleaning phase. The chemical bath, constituting a composition of 10\u0026ndash;30% phosphoric acid, 1\u0026ndash;10% hydrochloric acid, 1\u0026ndash;10% nitric acid, and 1\u0026ndash;10% proprietary surfactants, is a pivotal component of the chemo-polishing regimen. It is of paramount importance to rigorously maintain the bath temperature at a constant 75\u0026deg;C throughout the procedure, as deviations in temperature could lead to contamination of the chemical bath. Furthermore, agitation emerges as a critical element in the chemo-polishing protocol, effectively dispersing localized heat generated during the electropolishing phase. In the conducted experiments, agitation was meticulously executed through the utilization of a 20 mm magnetic stirrer set at 200 rpm. Following a 30-minute dissolution period, the samples were meticulously rinsed in distilled water.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Electroless Nickel Plating\u003c/h2\u003e \u003cp\u003eIn the domain of electroless nickel plating, it is customary to employ three distinct types of solutions. The pivotal determinant in the deposition of nickel lies in the concentration of phosphorus within these solutions. In the scope of our specific investigation, we utilized electroless nickel plating solutions classified into three categories: low phosphorus (ONE PLATE 3001), mid phosphorus (ONE PLATE 1001), and high phosphorus (ONE PLATE 2001). These solutions were procured from Plating International Inc., recognized for their stability, characterized by pH values within the range of 5 to 6. It is imperative to ensure the pristine condition of the sample prior to commencing the deposition process, as any surface impurities may detrimentally affect the quality of deposition and impede the adhesion of the nickel coating. Therefore, meticulous cleansing of the substrate, free from any extraneous debris, oils, greases, or oxide layers, is a prerequisite. So, it is required that the sample pass through the standard cleaning process. Once this preparatory phase is concluded, the sample is ready to undergo activation.\u003c/p\u003e \u003cp\u003eTo guarantee optimal adhesion for subsequent plating, certain metals necessitate surface activation[\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. In our experiment, the sample underwent activation through immersion in a Woods nickel strike solution while being subjected to a direct current (DC) of 5V for a duration of 30 seconds. The plating procedure is conducted immediately subsequent to activation. The maintenance of an ideal temperature is of paramount importance during the electroless plating process, as any slight deviation in temperature could trigger an exothermic reaction with the potential to compromise the integrity of the samples. The recommended temperature for the bath solution in the case of low and medium phosphorus is 90\u0026deg;C, while for high phosphorus solutions, it is set at 85\u0026deg;C. The deposition time allocated for all samples was standardized at 30 minutes.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eL9 Taguchi design of experiment (TDOE)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDOE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePhosphorus Content\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSurface Finish\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOrientation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTemperature\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eElec-Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXY Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u0026thinsp;+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChem- Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAs-Built\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT \u0026minus;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eElec- Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT \u0026minus;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChem- Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u0026thinsp;+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAs-Built\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXY Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLow\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eElec- Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLow\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eChem- Polishing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eXY Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT \u0026minus;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLow\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAs-Built\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eYZ Plane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eT\u0026thinsp;+\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Taguchi Design of Experiment (TDOE)\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the course of our experimental investigation, we employed a Taguchi Design of Experiments (TDOE) methodology, which encompasses a series of controlled experiments, characterized by four parameters, each exhibiting three distinct levels. The first parameter under scrutiny pertains to the concentration of phosphorus within the electroless nickel solution, with categorizations ranging from low, medium, to high levels. The second parameter centers around the type of surface finishing applied to ameliorate surface roughness, namely Electropolishing (EP), Chem-Polishing (CP), and the inherent as-built surfaces. The third parameter addresses the configuration of the 3D part coordinate plane, which significantly influences the surface characteristics resulting from the selective laser melting process. The core objective of our study lies in elucidating the responses of different plane surfaces to the deposition process. Finally, the fourth parameter revolves around the temperature of the nickel solution, which necessitates an optimal bath temperature tailored to each level. Our aim is to discern the manner in which the nickel solution reacts to temperature fluctuations relative to the established optimum temperature. To optimize the quality of experiments while concurrently streamlining the allocation of time and resources, we have adopted a strategic approach encompassing a temperature range spanning five degrees Celsius both below and above the defined optimum temperature. Through the judicious application of TDOE orthogonal arrays, we have effectively curtailed the number of requisite experiments to a total of nine trials. This methodological approach not only ensures the efficient utilization of resources and time but also provides in-depth understanding about the effect of different parameters and correlation among them. provides in-depth understanding about the effect of different parameters and correlation among them.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULTS AND DISCUSSION","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Surface Roughness characterization after EP, CP, and as-built AM samples\u003c/h2\u003e \u003cp\u003eSurface characterization of the samples was conducted utilizing the KEYENCE Digital Microscope VHX-7000. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e summarizes different roughness parameters for the AM surface after three types of cleaning. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, present the outcomes of the electropolishing surface finishing technique, revealing a substantially flatter topography with diminished hills and peaks. The associated surface roughness parameters are: Ra\u0026thinsp;=\u0026thinsp;4.85 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;22.89 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;13.02 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;11.76 \u0026micro;m and Rv\u0026thinsp;=\u0026thinsp;11.13 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed, illustrate the surface finish post chem-polishing. The corresponding surface roughness measurements are as follows: Ra\u0026thinsp;=\u0026thinsp;11.65, Rz\u0026thinsp;=\u0026thinsp;56.84 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;17.79 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;33.33 \u0026micro;m and Rv\u0026thinsp;=\u0026thinsp;23.50 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ee-f, depict the surface topography of the as-built samples. The surface roughness parameters for the as-built specimens are as follows: Ra (arithmetic mean roughness)\u0026thinsp;=\u0026thinsp;15.95 \u0026micro;m, Rz (the average maximum peak)\u0026thinsp;=\u0026thinsp;86.99 \u0026micro;m, RzJIS (Ten-point mean roughness)\u0026thinsp;=\u0026thinsp;38.54 \u0026micro;m, Rp (Maximum profile peak)\u0026thinsp;=\u0026thinsp;40.73 \u0026micro;m,and Rv (Maximum profile valley depth)\u0026thinsp;=\u0026thinsp;46.26 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Figures\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e suggests that surface topography and roughness changed significantly after chempolishing and electropolishing. Figures\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e suggests that surface topography and roughness changed significantly after chempolishing and electropolishing.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Surface Roughness characterization after Nickel Plating\u003c/h2\u003e \u003cp\u003eTo gain the insight about the role of surface treatment method and different coating parameters we investigated the 9 samples prepared as per the Taguchi Design of experiment scheme (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e shows the topography of different DOE samples, whereas Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e summarizes the roughness data on each sample quantitatively. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ea in our study portrays the outcomes of Design of Experiment (DOE) #1, where a specific set of experimental parameters was employed (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). These parameters encompassed the utilization of a high phosphorus nickel solution, an electropolished surface finish, orientation within the XY plane, and an elevated temperature exceeding the optimum by 5\u0026deg;C. (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e)Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eb, denoting DOE#2, features a distinct combination of experimental parameters involving a high phosphorus nickel solution, chem-polished surface finish, alignment along the YZ plane, and an optimal temperature setting (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). The resultant surface roughness measurements are as follows: Ra\u0026thinsp;=\u0026thinsp;10.90 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;49.993 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;34.61 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;23.1 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;26.89 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;37.03 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;49.99 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;12.90 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). In Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ec, we present the outcomes of DOE#3, executed with the utilization of a high phosphorus nickel solution, an as-built surface finish, alignment along the XZ plane, and a temperature setting lower than the optimum by 5\u0026deg;C. The measurements of surface roughness revealed the following values: Ra\u0026thinsp;=\u0026thinsp;15.7639 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;70.21 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;19.22 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;35.01 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;35.20 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;35.63 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;70.23 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;18.77\u0026micro;m.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ed, representing DOE#4, comprises parameters involving a mid-phosphorus nickel solution, an electropolished surface finish, alignment along the YZ plane, and a temperature set lower than the optimum by 5\u0026deg;C. The surface roughness characteristics of this configuration resulted in: Ra\u0026thinsp;=\u0026thinsp;15.15 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;67.91 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;36.42 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;38.38 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;29.5267 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;43.58 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;67.94 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;18.21 \u0026micro;m. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ee, representing DOE#5, encapsulates an experimental framework characterized by the use of a mid-phosphorus nickel solution, chemo-polished surface finish, alignment along the XZ plane, and an elevated temperature surpassing the optimum by 5\u0026deg;C. Surface roughness measurements for this setup yielded the following results: Ra\u0026thinsp;=\u0026thinsp;14.59 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;73.4 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;36.18 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;32.95 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;40.45 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;44.43 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;73.4 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;17.475 \u0026micro;m. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ef, representative of DOE#6, outlines a specific combination of parameters that incorporates a mid-phosphorus nickel solution, as-built surface finish, alignment along the XY plane, and the optimal temperature. The corresponding surface roughness measurements are as follows: Ra\u0026thinsp;=\u0026thinsp;17.56 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;84.77 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;32.82 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;46.77 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;38.03 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;50.1 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;84.81 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;21.0 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eg corresponds to DOE#7, characterized by the use of a low phosphorus nickel solution, an electropolished surface finish, alignment along the XZ plane, and the optimal temperature setting. Surface roughness measurements for this particular configuration revealed the following values: Ra\u0026thinsp;=\u0026thinsp;18.54 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;87.49 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;17.44 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;46.06 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;41.42 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;25.57 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;87.54 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;22.22 \u0026micro;m. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eh, emblematic of DOE#8, incorporates a set of parameters that entail a low phosphorus nickel solution, chemo-polished surface finish, alignment along the XY plane, and the temperature setting at the optimum level. The associated surface roughness characteristics are as follows: Ra\u0026thinsp;=\u0026thinsp;17.44 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;71.88 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;20.65 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;32.87 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;39.01 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;55.84 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;71.9 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;20.44 \u0026micro;m. Finally, Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ei represents DOE#9, wherein the experimental parameters encompass the utilization of a low phosphorus nickel solution, an as-built surface finish, alignment along the YZ plane, and a temperature exceeding the optimum by 5\u0026deg;C. The surface roughness measurements for this configuration resulted in the following values: Ra\u0026thinsp;=\u0026thinsp;11.30 \u0026micro;m, Rz\u0026thinsp;=\u0026thinsp;51.26 \u0026micro;m, RzJIS\u0026thinsp;=\u0026thinsp;19.56 \u0026micro;m, Rp\u0026thinsp;=\u0026thinsp;26.08 \u0026micro;m, Rv\u0026thinsp;=\u0026thinsp;25.17 \u0026micro;m, Rc\u0026thinsp;=\u0026thinsp;25.49 \u0026micro;m, Rt\u0026thinsp;=\u0026thinsp;51.26 \u0026micro;m, and Rq\u0026thinsp;=\u0026thinsp;13.66 \u0026micro;m (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Scanning electron microscope (SEM)\u003c/h2\u003e \u003cp\u003eIn high phosphorous solution (Figs.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ea ,\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eb, and \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ec) an approximate phosphorus concentration of up to 11% per deposition is observed. The primary objective of the coating is to maintain an amorphous structure, characterized by the absence of grain boundaries or phase boundaries, effectively mitigating the creation of initiation sites for corrosion. The mid phosphorous solution (Figs.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ed ,\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ee, and \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ef) provide evidence of robust adhesion and elevated plating hardness in the context of deposition on an as-built sample. Elemental analysis performed on the sample surface reveals an approximate phosphorus concentration of around 8% per deposition. Notably, the low phosphorous solution (Figs.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eg ,\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003eh, and \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003ei) in certain instances, observations indicate a phosphorus concentration of less than 5%, coupled with an inconsistent distribution pattern.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Scratch testing\u003c/h2\u003e \u003cp\u003eThe utilization of scratch testing serves as a fundamental technique for the comprehensive analysis and characterization of mechanical wear behaviors. The meticulous application of precisely defined scratches, performed in a consistent and reproducible fashion, becomes of paramount importance in the pursuit of surface wear resistance characterization. In the scope of our study, we opted for the standard 10 N scratch test methodology, conducted on samples coated with nickel (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e). Each of the nine samples (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was subjected to scratch testing (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ea-f). We were successful in obtaining clear scratch on nickel coated sample with high phosphorous content (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ea-c), medium phosphorous content (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ed-f), and low phosphorous content (Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003eg-i). However, a major challenge was in analyzing different scratches. The acquisition of precise measurements of the scratch width from the microscopic imagery was difficult due to the scratch's inconsistent width. Consequently, the methodology has been adapted to calculate the projected area of the scratch, which is then divided by its length to achieve a standardized measure (Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003ea).\u003c/p\u003e \u003cp\u003eIn the realm of image segmentation, the Segment Anything Model (SAM), developed by Meta, previously known as Facebook, has been employed. As a foundational model for segmentation, SAM has undergone training on a dataset encompassing 11\u0026nbsp;million images and in excess of one billion masks. The architecture of SAM is tripartite, consisting of an image encoder, a prompt encoder, and a mask decoder. The strength of SAM lies in its dual utility, offering both a no-code and a code-based solution. For the purposes of our experiment, the no-code, fully online option was selected. Subsequent to this, we applied denoising and thresholding processes using ImageJ to refine the results (example shown in, Fig.\u0026nbsp;\u003cspan refid=\"Fig10\" class=\"InternalRef\"\u003e10\u003c/span\u003eb). Once we have performed instance segmentation and thresholding on the scratch, we proceed to determine the material's level of hardness using a formula.\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$Hs = 8P/\\varPi {w}^{2}$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eWhere,\u003c/p\u003e \u003cp\u003eHs\u0026thinsp;=\u0026thinsp;Scratch hardness number (MPa)\u003c/p\u003e \u003cp\u003eP\u0026thinsp;=\u0026thinsp;Normal force (N)\u003c/p\u003e \u003cp\u003ew\u0026thinsp;=\u0026thinsp;scratch width\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eUpon a meticulous analysis of the results derived from the 10 N scratch test, a conspicuous enhancement in scratch resistance was observed both prior to and subsequent to the test. As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e, it is discernible that Design of Experiment (DOE) #2 and #7 exhibited a substantial augmentation in scratch resistance, reaching an impressive increase of up to 50%. Furthermore, DOE #4, #5, #8, and #9 displayed a marked improvement in surface hardness, manifesting enhancements that ranged from 51\u0026ndash;86%. Of notable significance, DOE #6 exhibited the most substantial advancement in surface hardness, registering an impressive escalation of 128%. However, it is worth mentioning that the remaining experiments failed to yield any substantial improvements in surface hardness. Hardness data before and after nickel coating has been summarized in Fig.\u0026nbsp;\u003cspan refid=\"Fig11\" class=\"InternalRef\"\u003e11\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSurface Hardness before and after Ni coating\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDOE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHardness before Ni deposition\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHardness after Ni deposition\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e125.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e332.64\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e119.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e338.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e207.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e587.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e218.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e610.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e194.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e538.22\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e297.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e890.48\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e219.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e643.89\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e233.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e660.62\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e269.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e815.58\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.5 Taguchi Analisis\u003c/h2\u003e \u003cp\u003eMulti-plots serve as a visualization tool for elucidating the impacts of numerous factors on a response variable (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003e). Within these plots, the presentation encompasses both main effects and interaction effects of the factors on the response variable (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003e). The main effects delineate the individual influence of each factor on the response variable, while the interaction effects depict the collective impact of two or more factors on the response variable. Phosphorous level impacted significantly (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003ea); high Phosphorous conetent appear to yield low hardness as compared to the medium and low phosphorous content. Interestingly, electropolish and chempolish surface treatment yielded similar effect (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003eb). The unpolished surface behaved very differently (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003ea). The surface orientation and temperature factor\u0026rsquo;s level impact was relatively weaker (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d). Different sample orientation produced different impact (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003ec); XY orientation behaved significantly different than that of XZ and YZ orientation (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003ec). Temperature effect was similar for level T and T\u0026thinsp;+\u0026thinsp;5, and it was different as compared to T-5 (Fig.\u0026nbsp;\u003cspan refid=\"Fig12\" class=\"InternalRef\"\u003e12\u003c/span\u003ed). We also studied the strength of interaction between two parameters. All potential interactions between pairs of two factors are computed (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003e.a). The interaction pairs are presented in a descending order based on their Severity Index (SI), which is expressed on a scale from 0 to 100%. In cases involving interactions among pairs of factors with 3 levels, the Severity Index (SI) is indicative of the highest angle within the array of feasible combinations of line segments (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003e.a). Interaction data shows relative independence of a factor in relation to other factor. The highest interaction strength of 92.78 was observered between the orientation and temperature; it means changing orientation will necessiate adjustment in the plating temperature for the desired results (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003ea). On the other hand, low severity index of 6.92 phosphorous and surface finish interaction shows their independence from each other. We also investigated the impact of individual factor on film hardness (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003eb). Phosphorus content is main factor in deciding the nickel coating hardness (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003eb). This result is in line with the prior literature relating the phosphorous content to the hardness of the nickel coating (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003eb). Interestingly, surface finishing method was the second most important factor (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003eb). This result is of critical importance in the light of the degree of complexity involved in AM geometry. Hardness is highest for the As built surface. The reason is that high roughness enable creating better grip of the coating material on the surface (Fig.\u0026nbsp;\u003cspan refid=\"Fig13\" class=\"InternalRef\"\u003e13\u003c/span\u003eb), this result is consistent with the prior literature defining the impact of roughness on the film adhesion.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWe also employed Taguchi Design of experiment analysis to investigate the combination of parameters that will lead to the highest hardness. The optimal table represent the predictive equation delineating the anticipated performance under optimal conditions as well as any conceivable alternative conditions. The numerical values presented in the table are derived from computations conducted under the optimal condition, a state determined by the chosen quality characteristic for analysis. Conventional practice dictates the inclusion of only statistically significant factors (without pooling) in the computation of anticipated performance, aligning with established analytical methodologies. In the context of this experiment, The optimal condition for achieving the highest hardness is identified as a low-phosphorus nickel solution, coupled with a as-built surface finish, XY orientation, and a solution temperature of 90 degrees Celsius.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. CONCLUSION","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThis study explores the utilization of electropolishing (EP) and chempolishing (CP) techniques for the removal of surface roughness, coupled with the subsequent application of electroless nickel plating as a protective layer coating on stainless-steel samples fabricated through additive manufacturing. These findings encapsulate the principal outcomes of the investigation.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eThe process of electropolishing exhibits a notable capability for achieving high-quality surface finishing, characterized by the rapid removal of material. Nevertheless, it is essential to acknowledge that this method is not without its limitations, particularly in terms of achieving uniformity and consistency across surfaces. In contrast, chempolishing emerges as a compelling alternative, primarily due to its capacity to uniformly remove material and impart smoothness to both internal and external surfaces.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eElectroless nickel deposition, as a plating technique, proves to be a highly suitable choice for enhancing the properties of stainless-steel samples generated through additive manufacturing. Nickel, with its inherent attributes, offers superior wear resistance, as corroborated by scratch testing, which has demonstrated that nickel-plated samples exhibit up to twice the resistance compared to their non-plated counterparts. Furthermore, the utilization of a high-phosphorus electroless nickel solution presents an additional advantage in terms of augmenting corrosion resistance.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eIt is pertinent to emphasize that the geometrical characteristics of the printed component play a pivotal role in influencing the surface finishing process. To attain a lustrous and impeccably smooth surface characterized by exceptional hardness and corrosion resistance, it may become imperative to employ a sequence of successive surface finishing techniques.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eIn conclusion, it has been observed that the optimal combination yielding the highest surface hardness involves the utilization of a low-phosphorus nickel solution, along with a built surface finish, XY orientation, and a solution temperature of 90 degrees Celsius\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCompeting Interests\u003c/h2\u003e \u003cp\u003eFinancial interests: Authors declare they have no financial interests\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis research was funded by National Science Foundation-CREST Award, grant number HRD- 1914751, Department of Energy/ National Nuclear Security Agency (DE-FOA-0003945), the Department of Energy\u0026rsquo;s Kansas City National Security Campus. The Department of Energy\u0026rsquo;s Kansas City National Security Campus is operated and managed by Honeywell Federal Manufacturing \u0026amp; Technologies, LLC under contract number DE-NA0002839 and The NASA MUREP Institutional Research Opportunity Grant under Cooperative Agreement #80NSSC19M0196.\u003c/p\u003e\u003ch2\u003eAuthor contributions\u003c/h2\u003e \u003cp\u003eThe inception of the research idea was attributed to Pawan Tyagi. Experimental procedures were executed by Wondwosen, Dan, and Pablo. Subsequently, the composition of the manuscript fell under the responsibility of Wondwosen, with subsequent critical evaluation undertaken by both Pawan Tyagi and Kate Klein. Pawan Tyagi contributed experimental data pertinent to chemo-polishing and electropolishing procedures. Additionally, the provision of experimental samples was facilitated by Lucas Rice.\u003c/p\u003e\u003ch2\u003eData Availability:\u003c/h2\u003e \u003cp\u003eData used in this paper will be made available upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGovekar E, Jeromen A, Kuznetsov A, Kotar M, Kondo M (2018) Annular laser beam based direct metal deposition. Procedia Cirp 74:222\u0026ndash;227\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGardan J (2017) Additive manufacturing technologies: state of the art and trends. Additive Manuf Handb pp. 149\u0026ndash;168\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBourell D, Wohlers T (2020) Introduction to additive manufacturing. Additive Manuf Processes 24:3\u0026ndash;10\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGibson I et al (2021) Additive manufacturing technologies. 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William Andrew\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHajdu J, Zabrocky S (2000) The future of electroless nickel. Met Finish 98(5):42\u0026ndash;46\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang L, Li J, Liu H (2011) A simple process for electroless plating nickel\u0026ndash;phosphorus film on wood veneer. Wood Sci Technol 45:161\u0026ndash;167\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKiguchi M (2017) Surface modification and activation of wood. Chemical modification of lignocellulosic materials. Routledge, pp 197\u0026ndash;227\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"the-international-journal-of-advanced-manufacturing-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jamt","sideBox":"Learn more about [The International Journal of Advanced Manufacturing Technology](https://www.springer.com/journal/170)","snPcode":"170","submissionUrl":"https://submission.nature.com/new-submission/170/3","title":"The International Journal of Advanced Manufacturing Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Additive manufacturing, electroless nickel, scratch test, 3D printing, Laser metal sintering","lastPublishedDoi":"10.21203/rs.3.rs-4372680/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4372680/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eElectroless coating brings the advantage of providing films on the complex geometry of additively manufactured components. However, there is a knowledge gap about the impact of AM part surface and postprocessing parameters on the quality of electroless coating. This study explores the application of three solution-based surface finishing techniques on the microstructure and surface hardness of additively manufactured stainless steel components coated with electroless nickel films. Given that AM techniques for metal parts often yield surfaces with inherently rough textures and differences in properties along the different planes, we investigated their relationship with nickel coating. To mitigate the impact of surface irregularities on electroless nickel coating quality, this research evaluated the effectiveness of chemical polishing (CP) and electropolishing (EP) as post-processing treatments for AM stainless steel. Characterization of the treated samples was conducted using the analytical Digital Microscope, Scanning Electron Microscope (SEM), and scratch tester. Additionally, the study incorporated an instant segmentation machine learning algorithm to overcome image analysis challenges. The findings indicate that EP and CP significantly improve surface smoothness, decreasing the arithmetical mean height (Ra) by as much as 4 \u0026micro;m and 10 \u0026micro;m, respectively. Furthermore, the nickel-coated AM samples demonstrated an enhancement in scratch resistance, exhibiting up to a two-fold increase in surface hardness compared to their as-built counterparts. Taguchi design of experiment was applied to investigate the effect of process parameters. This study provides insights for developing improved surface quality and acquiring new properties via the coating process to make AM parts suitable for challenging environments and novel applications.\u003c/p\u003e","manuscriptTitle":"Solution-based Post-processing and Electroless Nickel Plating Parameters Impacting the Microstructure and Hardness of Nickel-Plated L-shaped Additively Manufactured Steel Components.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-15 22:42:38","doi":"10.21203/rs.3.rs-4372680/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revisions Needed","date":"2024-07-17T13:06:47+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-05-27T08:57:11+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-07T15:09:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-06T23:46:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"The International Journal of Advanced Manufacturing Technology","date":"2024-05-05T13:41:17+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"the-international-journal-of-advanced-manufacturing-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jamt","sideBox":"Learn more about [The International Journal of Advanced Manufacturing Technology](https://www.springer.com/journal/170)","snPcode":"170","submissionUrl":"https://submission.nature.com/new-submission/170/3","title":"The International Journal of Advanced Manufacturing Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"64642232-81da-4eb1-9bd5-9dbb04d5dd9d","owner":[],"postedDate":"May 15th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-08-12T16:07:37+00:00","versionOfRecord":{"articleIdentity":"rs-4372680","link":"https://doi.org/10.1007/s00170-024-14217-z","journal":{"identity":"the-international-journal-of-advanced-manufacturing-technology","isVorOnly":false,"title":"The International Journal of Advanced Manufacturing Technology"},"publishedOn":"2024-08-06 15:57:06","publishedOnDateReadable":"August 6th, 2024"},"versionCreatedAt":"2024-05-15 22:42:38","video":"","vorDoi":"10.1007/s00170-024-14217-z","vorDoiUrl":"https://doi.org/10.1007/s00170-024-14217-z","workflowStages":[]},"version":"v1","identity":"rs-4372680","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4372680","identity":"rs-4372680","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}