Experimental and numerical study on tribological behavior and machinability in titanium indirect cryogenic machining with minimum quantity lubrication

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In this study, cryogenic machining was applied to a titanium alloy with minimum quantity lubrication (MQL), and the tribological and machining performance were evaluated. As side-down milling was performed, the effects of cryogenic cooling and MQL were experimentally and numerically investigated with long machining distances (40, 000 mm), and the cutting force, tool wear, and tool temperature were analyzed. Compared to the wet condition, under the cryoMQL condition, which represents the simultaneous application of cryogenic cooling and MQL, the cutting force and flank wear length decreased by up to 17.7% and 46.4%, respectively. The cryogenically cooled and lubricated cutting tool enhanced the tribological performance, slowing tool wear. The reduced surface friction of the tool and tool wear decreased the frictional force and changed the trend of the cutting force according to the machining distance. The cryoMQL milling was simulated using DEFORM software. In the numerical study, a decrease in the tool temperature, which affects the reduction in cutting force and tool wear, was observed under cryoMQL conditions. The maximum tool temperature was reduced by 46.5% compared with that under wet conditions. Cryogenic machining Minimum quantity lubrication Titanium alloy Cutting force Tool wear 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 Highlights The indirect cryogenic cooling with minimum quantity lubrication (cryoMQL) of the Ti milling process reduces cutting force and tool wear compared to the wet milling process. The indirect cryoMQL method resulted in over a 17.7% reduction in cutting force because of the tool frictions and slow down tool wear progression. The indirect cryoMQL method resulted in a flank wear length that was 46.6% shorter than under wet conditions after 400 machining passes. The numerical simulation model predicts a 46.5% reduction in the maximum tool edge temperature due to indirect cryoMQL compared to wet conditions. 1. Introduction Titanium materials are widely used in various industries because of their excellent mechanical and chemical properties. They exhibit a high strength-to-weight ratio and good corrosion resistance [ 1 , 2 ]. These properties can improve the performance of aerospace components by reducing their weight and increasing the applicability of implants to the human body. However, these materials have poor thermal characteristics such as low thermal conductivity and specific heat, which cause a decrease in machinability. Low specific heat generates excessive heat during the plastic deformation of materials during machining. Low thermal conductivity causes heat accumulation, resulting in a high cutting temperature, which, if continuously applied to the cutting tool, accelerates wear and decreases productivity [ 3 , 4 ]. Several advanced machining methods, including cryogenic machining, have been applied to enhance the machinability. Cryogenic machining is a process that uses cryogenic coolants as cutting fluids and has been studied to improve tool life by reducing the cutting temperature [ 5 , 6 ]. Turning experiments were performed on a titanium alloy by spraying LN 2 (liquid nitrogen) to demonstrate that the application of LN 2 increases tool life [ 7 , 8 ]. Wang and Rajurkar [ 9 ] conducted cryogenic machining of Inconel and tantalum and observed an improvement in tool life. However, under certain conditions, cryogenic machining adversely affects machinability [ 10 , 11 ]. Chaabani et al. [ 10 ] observed that during the turning of Inconel 718, there was greater flank wear under cryogenic conditions using LN 2 and LCO 2 (liquid carbon dioxide) than under wet conditions. Agrawal et al. [ 11 ] performed cryogenic turning of Ti-6Al-4 V at various cutting speeds; at cutting speeds of up to 90 m/min, flank wear occurred faster than under wet machining. This phenomenon was caused by the hardness of the work material, which increased as a result of cryogenic cooling. Various studies have been conducted to eliminate the adverse effects of changing spraying systems and applying additional lubricants [ 12 , 13 ]. Spraying systems are used to prevent contact between the cryogenic coolant and working material [ 14 , 15 ]. Islam et al. [ 16 ] applied an internal system using a cutting tool with internal channels for cryogenic coolants in the machining of hardened steels. The coolants were sprayed toward the tool tip, and the internal cryogenic cooling enhanced the machinability by reducing the flank wear length. Gan et al. [ 17 ] developed an internal cooling turning tool suitable for cryogenic cooling processes and conducted various cutting experiments to validate it. Their results confirmed that internal cooling improves cooling efficiency, effectively enhancing surface quality and reducing tool wear. Bogajo et al. [ 18 ] presented an indirect system that circulates cryogenic coolants inside a cutting tool during ASTM F-1537 turning. The tool tip was cryogenically cooled via conduction without direct contact with LN 2 , which decreased the cutting force. The minimum quantity lubrication (MQL) method was studied in conjunction with cryogenic machining [ 19 , 20 ]. Machining processes with the application of MQL have successfully achieved reductions in tool wear, surface roughness, and improvements in dimensional accuracy [ 21 ]. Suhaimi et al. [ 22 , 23 ] applied MQL to the indirect cryogenic machining of a titanium alloy, which significantly reduced the cutting forces and tool wear compared to other cryogenic machining technologies that use an internal system and an external nozzle. Zou et al. [ 19 ] demonstrated that the application of MQL during cryogenic machining was effective in reducing tool wear and surface roughness. However, most previous studies have been performed using relatively short machining times and distances; thus, research on cryogenic machining characteristics under extremely long machining distances is insufficient. Machining is a long-term process in the manufacture of various industrial parts. Therefore, it is necessary to analyze the effects of cooling and lubrication on tribological behavior and machinability based on the removal of a large volume of material. Numerical studies must also be conducted to obtain a clear understanding of the machining characteristics. In this study, a cryogenic milling experiment was performed on a Ti alloy (Ti-6Al-4V) over a long machining distance. LN 2 was sprayed using an indirect system and MQL was applied by spraying lubricants through an external nozzle. The cutting force and tool wear length were determined based on the machining distance. The effects of cryogenic cooling and lubrication on machinability were identified based on experimental data. The effects were further analyzed using numerical simulations, and the tool temperature was predicted. The machining characteristics were thoroughly investigated based on the simulation results. 2. Experimental setup A cryogenic milling experiment was performed using an indirect spraying system, in which LN 2 was used as the cryogenic coolant. A tungsten carbide tool was used, and channels for LN 2 were formed inside a commercial milling tool (F1200, Walter) for the indirect system. The coolant circulating inside the cutting tool was sprayed outward through holes at a distance from the tool tip. The shape of the cutting tool is illustrated in Fig. 1 . The MQL method was also applied to enhance the frictional characteristics of the cutting tool surface [cryoMQL (cryogenic + MQL)]. A vegetable-oil-based lubricant was sprayed with the external nozzle directed toward the tool tip. The coolant and lubricant flow rates were controlled at pressures of 4 and 7 bar, respectively. The target work material was Ti-6Al-4V. A 100 mm × 100 mm × 100 mm block-type specimen was manufactured and cut using side-down milling. A machining center (HTC-1000, HANKUK) was designed to spray the coolant and lubricant stably. The machine passed through the spindle for LN 2 and a system that controlled the coolant and lubricant pressures. The experimental setup is illustrated in Fig. 2(a). The experiments were conducted over excessively long machining distances. Machining distances of up to 400 passes were applied; a machining distance of 100 mm was defined as one pass. Considering the specimen size, the machining paths shown in Fig. 2(b) were applied. A feed time was available between one pass and the next because the cutting tool moved to the starting point of the next pass after machining in the previous pass. The feed time was relatively long for 100, 200, and 300 passes owing to the long feed distance. The cutting force was measured during the machining. A force dynamometer (9139AA, Kistler) was attached to the working material. The tool wear was investigated after 400 machining passes. The tool flank wear length was measured using a microscope (Z16APO, Leica). A cutting speed of 90 m/min, an axial depth of 5 mm, and a radial depth of 1 mm were used. Two feeds (0.07 and 0.08 mm/tooth) were adopted. The experimental conditions are listed in Table 1 . For comparative analysis, wet machining was also performed, and the effects of cryogenic cooling and lubrication on tribological behavior (frictional characteristic on tool surface) and machinability were investigated based on the cutting force and tool wear. Table 1 Experimental condition of end milling Work material Cooling condition Tool diameter (mm) Cutting speed (m/min) Radial depth (mm) Axial Depth (mm) Feed (mm/ tooth) Machining distance (pass) Ti-6Al-4V Wet 16 90 1 5 0.07 0.08 1–400 CryoMQL 3. Numerical modeling Finite element simulation was conducted using DEFORM software to numerically study the cryogenic milling characteristics. DEFORM is a specialized simulation software for manufacturing processes, particularly machining, and includes a machining module that can simulate various machining operations [ 24 ]. A milling module was used in this study. A milling tool with the same shape as that used in the experiment was used. Certain parts of the work material, near the cutting area, were implemented. The mesh was generated using the DEFORM automatic mesh-generation method with a minimum element size of 0.042 mm. The positions of the work material elements farthest from the cutting edge were fixed. Under the wet condition, the initial temperatures of all the elements were set at room temperature (25 ℃). Conversely, under the cryoMQL condition, a cryogenic temperature of -176 ℃ was applied to the cutting tool, because the internal circulation of LN 2 lowered the cutting tool temperature to a level similar to that of LN 2 . The cryogenic temperature was determined by measuring the temperature of the sprayed LN 2 . The model setup is illustrated in Fig. 3 . The mechanical and thermal properties of Ti-6Al-4V and tungsten carbide embedded in the software were applied to the cutting tool and work material. Machining was simulated by rotating the cutting tool, and the cutting force and tool temperature were predicted. The cutting force and temperature were closely correlated. In machining, the plastic deformation of the material generates plastic stress and a cutting force, which determine the heat generated at the shear plane and is the main source of the cutting temperature. Therefore, tool temperature was predicted under a simulated cutting force that matched the experimental results. The numerical study followed the flowchart shown in Fig. 4 . 4. Result and discussion 4.1 Experimental cutting force and tribological behavior The cutting forces were measured in real-time during cryogenic milling. The resultant forces were obtained from data measured in the x-, y-, and z-directions. The experimental results at each pass were derived via root mean square (RMS) analysis (Fig. 5 ). In machining, the cutting force can be affected by various factors such as the work material temperature, cutting temperature, and tool wear. An increase in temperature during machining can lower the cutting force by weakening the work material. The evolution of tool wear can cause a geometrical deformation of the cutting tool, thereby increasing the cutting force. The measurement data were analyzed by considering these phenomena. The analysis was performed at a feed rate of 0.07 mm/tooth. Under wet conditions, the cutting force increased rapidly as the machining distance increased to 20 passes. In titanium machining, which generates high temperatures, the length of flank wear can rapidly increase at the start of machining. Thus, the increase in cutting force at short machining distances appears to be caused by tool wear. After 20 passes, the rate of increase in the cutting force decreased. However, abrupt changes were observed at certain machining distances (100, 200, and 300 passes), and the force initially increased and then decreased significantly. The feed time for the next machining process was relatively long at 100, 200, and 300 passes, and the tool temperature that was increased by machining decreased. The mechanical properties of the tool could become unstable owing to the large temperature change, and the impact of contact between the tool and work material when machining was restarted may have induced tool deformation. The deformed tool geometry presumably caused sudden increases and decreases in the cutting force. However, under the cryoMQL conditions, there was no significant increase in the cutting force during machining for up to 100 passes. The cutting force slightly increased at short machining distances, but immediately decreased and remained low until 100 passes. Under these conditions, the cutting tool was cooled using LN 2 and the tool surface was lubricated. The decreased cutting temperature slowed the evolution of the tool wear and prevented an increase in the cutting force. Then, the minimum quantity lubricant in contact with the tool surface reduced surface friction, so the adequate lubrication enhanced the tribological performance, lowering cutting force. Abrupt changes in the cutting force were observed at 100 and 300 passes, similar to the wet conditions; the long feed time and reduced tool temperature were considered to be the causes. Regardless, the overall cutting force was less than that under wet conditions. Therefore, the simultaneous application of cryogenic cooling and MQL was suitable for reducing the cutting force. To compare the cutting forces based on cooling conditions, the cutting forces at different machining distances (1, 100, 200, 300, and 400 passes) were observed (Fig. 6 ). CryoMQL reduced the cutting force by up to 17.7% after 100 passes. Under both cooling conditions, the cutting force tended to increase with the machining distance. Increased tool wear may have induced this phenomenon because tool wear is proportional to the machining distance. At a feed rate of 0.08 mm/tooth, the cutting forces increased under both cooling conditions compared to that for a feed rate of 0.07 mm/tooth. An increase in feed rate indicates an increase in machining area. An enlarged machining area generates a large cutting force. Under wet conditions, the trend of the cutting force according to the machining distance was the same as that at a feed rate of 0.07 mm/tooth, but the range over which the cutting force fluctuated, increased. A large cutting force can increase the tool vibration, which affects the cutting force and causes force fluctuations. Under the cryoMQL conditions, the cutting force appeared irregular, and its tendency based on the machining distance was insignificant. The increased magnitude of cutting force may have contributed to this phenomenon. Generally, because MQL has a better lubrication effect than emerging floods under wet conditions, it can prevent an increase in the cutting force. However, the cutting temperature was reduced by the LN 2 which was sprayed, and the low temperature and change in the feed rate significantly improved the cutting force. The lubricant was not sufficient to reduce the cutting force, and the corresponding phenomena induced extreme tool vibrations with irregular fluctuations in the force. Consequently, the difference between the cutting forces under the wet and cryoMQL conditions was not large. Thus, the cooling and lubrication environments must be determined depending on the machining conditions, and the cryoMQL condition was considered to have a remarkable effect on the cutting force reduction at feed rates of less than 0.08 mm/tooth. 4.2 Experimental tool wear The faces of the tool flank under all cooling and machining conditions were captured after completion of machining at a distance of 400 passes (Fig. 7). Flank wear was observed under all conditions. The heat and stress generated continuously during machining can induce wear. Chipping was observed under all conditions except for the cryoMQL with a feed rate of 0.07 mm/tooth. Side-down milling is a process in which a tool is affected during each rotation. When a tool rotates and enters the work material, a large cutting force is generated when it encounters a large machining area. This can result in tool breakage under wet conditions. Furthermore, the tool temperature may fluctuate owing to heat from machining and cooling owing to coolants. The tool can undergo thermal shock due to a sudden change in temperature, leading to chipping. Conversely, no chipping was observed under the cryoMQL condition with a feed rate of 0.07 mm/tooth, where a lubricant was sprayed to reduce friction; this is an important factor for determining the frictional heat on the surface. MQL prevents thermal shock by decreasing the frictional heat, and cryogenic cooling can reduce the cutting temperature. Thus, the synergistic effect of LN 2 and the lubricant maintained a low tool temperature without an abrupt increase in the cutting temperature, and the reduced temperature fluctuation prevented chipping. However, this result was only applicable at a feed rate of 0.07 mm/tooth; chipping was observed at 0.08 mm/tooth. The probability of tool breakage increases when a large cutting force was applied at extremely low temperatures. To understand this phenomenon, the relationship between a large cutting force and a low tool temperature must be studied. This case is discussed detail in a numerical study of the tool temperature. Flank wear lengths were measured from the captured flank faces. Under each condition, five points were selected at equal intervals on the tool edge, and the average value of the five wear lengths was used for the comparative analysis (Fig. 8 ). The flank wear lengths under cryo-MQL conditions were shorter than those under wet conditions. Under cryoMQL conditions, the tool temperature decreased, delaying the evolution of wear. Because heat was applied to the cutting tool for an extended time owing to the long machining distance, the influence of the cooling conditions became evident. In particular, the minimum wear length was observed at a feed rate of 0.07 mm/tooth; the wear length under cryoMQL conditions was 46.4% less than that under wet conditions. Under these conditions, the cutting force was relatively small, which could induce a small stress and have a major effect on tool wear. Tool damage decreased when the cutting force was relatively small. Based on these results, the cryoMQL condition was considered effective in improving machinability in terms of tool wear. 4.3 Numerical cutting force and tribological behavior The cutting forces under wet and cryoMQL conditions were predicted using numerical simulations. During milling, the cutting force varies depending on the tool rotation angle and machining area. In down milling, the cutting force rapidly increased at the beginning of machining and then decreased as the tool rotates. To understand machining characteristics, the profile and maximum values of the resultant force were predicted, and the maximum resultant force for each condition was used as the simulation result. The machining conditions, which included a cutting speed of 90 m/min and a feed rate of 0.07 mm/tooth was applied. The numerical study focused on the effect of the cooling conditions, excluding the influence of wear. Thus, a sharp tool edge without wear was adopted, indicating that a machining distance of one pass was considered. The chip formation and strain obtained from the machining simulations are shown in Fig. 9. The experimental cutting force measured in one pass was used for validation, and the simulation results are shown in Fig. 10 . Under cryo-MQL conditions, the cutting force was lower than that under wet conditions. When the temperature of the tool surface was decreased by LN 2 , the surface adhesion decreased, which decreased the adhesive friction and frictional force on the tool surface. A change in frictional characteristics induced a decrease in the cutting force. The same result was observed in the experimental data; the maximum resultant force under the cryoMQL condition reduced by 6.1% compared to that under wet conditions. The decrease in tool temperature and the effect of MQL spraying effectively reduced the tool surface friction. It is difficult for an emerging flood to flow into the tool-chip interface under wet conditions; therefore, the effect of the MQL was apparently greater. A decrease in friction directly reduces frictional heat and delays tool wear. Thus, the improved adhesive friction reduced the cutting forces not only at one pass, but also at long machining distances, as indicated by the experimental data. 4.4 Numerical tool temperature The tool temperature was simulated during the side-down milling. A cutting speed of 90 m/min, a feed rate of 0.07 mm/tooth, and a machining distance of 1 pass were applied. Various factors generate heat during the machining process. Plastic deformation of the work materials increases the shear temperature, and the adhesive friction on the tool surface generates frictional heat; the sprayed LN 2 induces cryogenic heat. The heat applied to the cutting tool was predicted by considering the plastic stress in the shear zone and thermal properties of the cutting tool and work material. The plastic stress in titanium machining was simulated and considered. The temperature variation was visualized in the tool geometry, as shown in Fig. 11. The temperature varied depending on the position on the tool edge, and a large temperature increase was observed in the area near the tool tip and at a certain distance from the tip. During the milling process, the tool tip first made contact with the work material over a small machining area, generating high stress and resulting in a high temperature. Subsequently, chips were formed during the machining of the slides onto the tool surface. Frictional heat was generated by tool surface friction and sliding chips at a certain distance from the tool tip, as demonstrated by tool wear measurement results. When the faces of the tool flank were examined, chipping was observed in the middle of the tool edge, which is a region similar in location to where the temperature significantly increased in the simulation. Therefore, chipping can occur under the influence of increased temperatures. The maximum temperatures on the tool edge for each condition were compared to quantitatively analyze the effect of the cooling conditions (Fig. 12 ). Under the cryoMQL condition, a lower maximum temperature was confirmed compared to the wet condition; the temperature in Kelvin was reduced by 46.5%, and subzero temperature in degrees Celsius, was observed. Cryogenic cooling may have caused this decrease by reducing the initial tool temperature and heat generated. Regarding the measured tool wear, the cryoMQL condition with a feed rate of 0.07 mm/tooth minimized the flank wear length without chipping. Low temperatures improve the resistance to tool wear. The sprayed LN 2 maintained the cutting tool temperature continuously, thereby reducing the possibility of tool failure. Conversely, when a 0.08 mm/tooth feed rate was applied, chipping was observed to be the same as in the wet condition. Generally, the brittleness of a material increases as the temperature decreases, and brittle materials break under large forces. A cryogenically cooled cutting tool is relatively brittle and is exposed to a greater risk of breakage owing to the large feed rate, causing a large cutting force. Thus, applying a feed rate of 0.08 mm/tooth may have caused chipping despite the cryoMQL condition. Nevertheless, because tool wear tended to decrease under cryoMQL conditions, the temperature reduction enhanced machinability. Conclusion The effects of cryogenic cooling and MQL were studied experimentally and numerically during side-down milling using long machining distances. The cutting force, tool wear, and tool temperature were analyzed. The findings are summarized as follows. (1) The cryoMQL condition reduced the cutting force. The tool surface friction was reduced by decreasing the surface temperature and lubrication using MQL. Cryogenic cooling slowed the evolution of tool wear, preventing an increase in the cutting force owing to an increase in the machining distance. When a 0.07 mm/tooth feed rate was applied, the cutting force was reduced by up to 17.7% compared to the wet condition. (2) The cryoMQL condition with a low feed rate (0.07 mm/tooth) increased the resistance to chipping of the cutting tool. Continuous cooling by spraying LN 2 and low-friction heat reduced the possibility of thermal shock. (3) The simultaneous use of cryogenic cooling and MQL decreases the flank wear length. The rate of increase in the tool wear was reduced because the tool temperature was decreased by cryogenic cooling and the reduction in frictional heat. The flank wear length after 400 machining passes was 46.6% shorter than that under wet conditions. (4) The use of LN 2 and MQL decreased the numerical tool temperature. The maximum temperature on the tool edge was reduced by 46.5% compared with that under wet conditions. The temperature reduction had a remarkable influence on the decrease in cutting force and tool wear. Declarations Funding This work was supported by the Academic Promotion System Tech University of Korea and by research fund of Chungnam National University, and the "Regional Innovation Strategy (RIS)" through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE) (2021RIS-003). Conflicts of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Author information Authors and Affiliations Prof. Do Young Kim., Ph.D Department of Mechatronics Engineering, Chungnam National University, Daehak-ro 99, Yuseong-gu, Daejeon, Republic of Korea, 34134 Ju-Hyung Ha., Master Degree WorkerInSpace Inc., R&D Center, Jiphyeonjungang 2-ro, Republic of Korea, 30141 Min Gi Ha., M.S. course Department of Mechanical Convergence Engineering, Kyungnam University, Kyungnamdaehak-ro 7, Masanhappo-gu, Changwon-si, Gyeongsangnam-do, Republic of Korea, 51767 Prof. Dong Min Kim. Ph.D Department of Mechanical Design Engineering, Tech University of Korea, 237 Sangidaehak-ro, Siheung-si, Gyeonggi-do, Republic of Korea, 15073 Contributions Dongmin Kim was responsible for the study’s conception and design. Ju-Hyung Ha prepared the experiments and collected the data, while Doyoung Kim carried out the data analysis and wrote the initial draft of the manuscript. Min Gi Ha supported data analysis with Doyoung Kim on earlier versions. 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Nalbant, A review of cryogenic cooling in machining processes. Int. J. Mach. Tool. Manuf. 48 (2008) 947–964. https://doi.org/10.1016/j.ijmachtools.2008.01.008. Supplementary Files floatimage1.jpeg Graphical Abstract Cite Share Download PDF Status: Published Journal Publication published 03 Jun, 2025 Read the published version in The International Journal of Advanced Manufacturing Technology → Version 1 posted Editorial decision: Major Revisions Needed 19 Mar, 2025 Reviewers agreed at journal 21 Jan, 2025 Reviewers invited by journal 21 Jan, 2025 Editor assigned by journal 19 Jan, 2025 First submitted to journal 16 Jan, 2025 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. 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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-5817747","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":405263896,"identity":"3465da7c-814f-4cba-adda-7312867f9a72","order_by":0,"name":"Doyoung Kim","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Doyoung","middleName":"","lastName":"Kim","suffix":""},{"id":405263897,"identity":"5762cc3c-42f8-4ebe-b476-ce051304d9b4","order_by":1,"name":"Ju-Hyung Ha","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ju-Hyung","middleName":"","lastName":"Ha","suffix":""},{"id":405263898,"identity":"6b1dd965-ab0f-4e7c-b72d-3f36963c09cd","order_by":2,"name":"Min Gi Ha","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Min","middleName":"Gi","lastName":"Ha","suffix":""},{"id":405263899,"identity":"cbe7b9ef-2739-4396-b8f1-ca06e82d9d9b","order_by":3,"name":"Dongmin Kim","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIie3OsWoCMRjA8QQhLh/eGidfIRLodLavcsdBXLr1AUyRZhJc41scuDpEPrjpSlfFQV1uctAXaBs7dBHvdHPIH7J85Jd8hIRCj1hJNUm/+WhKSOt/6GcN5MhiOjO3E3/BMkXz4lbSKfFjDoAtuZ1IcVrEPdLGHZ0trpPu57vZAEf2VIBMbaX6GpSgeXWdiC/qiUA4EwSHfqdXQneuiSTIpfkjPy86OjQQv9jaOiUEA5mBc6nm/pe8hnTLpVmddJzwQr31rcsywyuxtDWkUw6rlX85icY450f3PJhG2X4/qSGXMX/uAqFQKBS67BfmdlmSUU5RDgAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-9303-7731","institution":"Tech University of Korea","correspondingAuthor":true,"prefix":"","firstName":"Dongmin","middleName":"","lastName":"Kim","suffix":""}],"badges":[],"createdAt":"2025-01-13 07:43:39","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5817747/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5817747/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00170-025-15774-7","type":"published","date":"2025-06-03T15:57:05+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":74583408,"identity":"5e9690ee-936e-4bd6-baa8-90a46f52fa55","added_by":"auto","created_at":"2025-01-23 16:12:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":529212,"visible":true,"origin":"","legend":"\u003cp\u003eShape of indirect cryogenic machining tool.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/8ab1c29f936330219fc52a0a.png"},{"id":74583873,"identity":"e64a2e5e-3456-403b-90d4-c377a24b1688","added_by":"auto","created_at":"2025-01-23 16:20:01","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":805981,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Experimental setup. (b) Machining path of end milling.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/b8fb8ce8f9ea69e6cf16d334.png"},{"id":74583449,"identity":"015059aa-8511-434f-adf2-8e4276a123ae","added_by":"auto","created_at":"2025-01-23 16:12:05","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":890062,"visible":true,"origin":"","legend":"\u003cp\u003eBoundary condition for the numerical simulation of cryogenic end milling.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/1d9fc86b68c67a0626f45145.png"},{"id":74583448,"identity":"14f3fd25-7223-4068-bdd7-618dbc853a70","added_by":"auto","created_at":"2025-01-23 16:12:05","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":325824,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of numerical simulation.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/060695d6dd77b8a4c340491d.png"},{"id":74583872,"identity":"5e35723b-b414-49da-990e-ff01ac0236fa","added_by":"auto","created_at":"2025-01-23 16:20:01","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":435158,"visible":true,"origin":"","legend":"\u003cp\u003eMeasured cutting forces according to machining distance.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/21b88accdf4822f1e664d432.png"},{"id":74583899,"identity":"ecae6401-d419-4053-b5e3-07104030f8c0","added_by":"auto","created_at":"2025-01-23 16:20:03","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":325868,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of cutting forces under different cooling and machining conditions at 1, 100, 200, 300, and 400 passes.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/3689c7355bee3230323dd833.png"},{"id":74584762,"identity":"be110e65-626f-4b7d-8d84-edf7b556385b","added_by":"auto","created_at":"2025-01-23 16:28:01","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":781254,"visible":true,"origin":"","legend":"\u003cp\u003eTool flank faces under wet [(a) 0.07 and (b) 0.08 mm/tooth feed] and cryoMQL [(c) 0.07 and (d) 0.08 mm/tooth feed] conditions at a machining distance of 400 passes.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/7c0baa9744fb3ca4e407d0e6.png"},{"id":74583396,"identity":"e11b63ac-98d1-4228-bdbb-d17ed3649f05","added_by":"auto","created_at":"2025-01-23 16:12:00","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":511044,"visible":true,"origin":"","legend":"\u003cp\u003eMeasured flank wear at a machining distance of 400 passes.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/bca6dec78837201ad58eea47.png"},{"id":74583441,"identity":"2cc7467c-238b-4c81-88ed-40dcffa94d7e","added_by":"auto","created_at":"2025-01-23 16:12:04","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":540398,"visible":true,"origin":"","legend":"\u003cp\u003eSide-down milling simulation under cryoMQL conditions for a feed rate of 0.07 mm/tooth and machining distance of 1 pass for (a) chip formation and (b) chip strain.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/b88580116aa5183f91231051.png"},{"id":74583900,"identity":"092a75e5-8bde-4cf8-b14c-004616e9451c","added_by":"auto","created_at":"2025-01-23 16:20:04","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":285445,"visible":true,"origin":"","legend":"\u003cp\u003eSimulated cutting forces for a feed rate of 0.07 mm/tooth and machining distance of 1 pass.\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/8f714a0d18a3c9618b1ea79e.png"},{"id":74583421,"identity":"53f17761-bb87-4055-bb80-c48fdf27f7e7","added_by":"auto","created_at":"2025-01-23 16:12:03","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":566148,"visible":true,"origin":"","legend":"\u003cp\u003eSimulated temperature variations in the cutting tool under (a) wet and (b) cryoMQL conditions with a feed rate of 0.07 mm/tooth.\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/5f4c26d27f104dee64dc2c8f.png"},{"id":74583438,"identity":"10cbb9f1-be81-4387-856c-5e93d78c0c5b","added_by":"auto","created_at":"2025-01-23 16:12:04","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":316960,"visible":true,"origin":"","legend":"\u003cp\u003eSimulated maximum tool temperatures under all cooling conditions.\u003c/p\u003e","description":"","filename":"12.png","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/c2260fc4b5dc2b48088d7443.png"},{"id":84242480,"identity":"b7f63f2e-6fb4-4806-be92-a470e357ffe9","added_by":"auto","created_at":"2025-06-09 16:07:50","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":8730276,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/800fefed-8dca-484d-b886-8a910e5c28b0.pdf"},{"id":74583409,"identity":"1463c1a9-5e53-4a51-a7f5-c1e69adbc96a","added_by":"auto","created_at":"2025-01-23 16:12:02","extension":"jpeg","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":104297,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eGraphical Abstract\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5817747/v1/04b04faf0bb3e6d27d2d4bf6.jpeg"}],"financialInterests":"","formattedTitle":"Experimental and numerical study on tribological behavior and machinability in titanium indirect cryogenic machining with minimum quantity lubrication","fulltext":[{"header":"Highlights","content":"\u003cul class=\"decimal_type\" start=\"50\"\u003e\n \u003cli\u003eThe indirect cryogenic cooling with minimum quantity lubrication (cryoMQL) of the Ti milling process reduces cutting force and tool wear compared to the wet milling process.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eThe indirect cryoMQL method resulted in over a 17.7% reduction in cutting force because of the tool frictions and slow down tool wear progression.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eThe indirect cryoMQL method resulted in a flank wear length that was 46.6% shorter than under wet conditions after 400 machining passes.\u003c/li\u003e\n \u003cli\u003eThe numerical simulation model predicts a 46.5% reduction in the maximum tool edge temperature due to indirect cryoMQL compared to wet conditions.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"1. Introduction","content":"\u003cp\u003eTitanium materials are widely used in various industries because of their excellent mechanical and chemical properties. They exhibit a high strength-to-weight ratio and good corrosion resistance [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. These properties can improve the performance of aerospace components by reducing their weight and increasing the applicability of implants to the human body. However, these materials have poor thermal characteristics such as low thermal conductivity and specific heat, which cause a decrease in machinability. Low specific heat generates excessive heat during the plastic deformation of materials during machining. Low thermal conductivity causes heat accumulation, resulting in a high cutting temperature, which, if continuously applied to the cutting tool, accelerates wear and decreases productivity [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral advanced machining methods, including cryogenic machining, have been applied to enhance the machinability. Cryogenic machining is a process that uses cryogenic coolants as cutting fluids and has been studied to improve tool life by reducing the cutting temperature [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Turning experiments were performed on a titanium alloy by spraying LN\u003csub\u003e2\u003c/sub\u003e (liquid nitrogen) to demonstrate that the application of LN\u003csub\u003e2\u003c/sub\u003e increases tool life [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Wang and Rajurkar [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] conducted cryogenic machining of Inconel and tantalum and observed an improvement in tool life. However, under certain conditions, cryogenic machining adversely affects machinability [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Chaabani et al. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] observed that during the turning of Inconel 718, there was greater flank wear under cryogenic conditions using LN\u003csub\u003e2\u003c/sub\u003e and LCO\u003csub\u003e2\u003c/sub\u003e (liquid carbon dioxide) than under wet conditions. Agrawal et al. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] performed cryogenic turning of Ti-6Al-4 V at various cutting speeds; at cutting speeds of up to 90 m/min, flank wear occurred faster than under wet machining. This phenomenon was caused by the hardness of the work material, which increased as a result of cryogenic cooling.\u003c/p\u003e \u003cp\u003eVarious studies have been conducted to eliminate the adverse effects of changing spraying systems and applying additional lubricants [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Spraying systems are used to prevent contact between the cryogenic coolant and working material [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Islam et al. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] applied an internal system using a cutting tool with internal channels for cryogenic coolants in the machining of hardened steels. The coolants were sprayed toward the tool tip, and the internal cryogenic cooling enhanced the machinability by reducing the flank wear length. Gan et al. [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] developed an internal cooling turning tool suitable for cryogenic cooling processes and conducted various cutting experiments to validate it. Their results confirmed that internal cooling improves cooling efficiency, effectively enhancing surface quality and reducing tool wear. Bogajo et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] presented an indirect system that circulates cryogenic coolants inside a cutting tool during ASTM F-1537 turning. The tool tip was cryogenically cooled via conduction without direct contact with LN\u003csub\u003e2\u003c/sub\u003e, which decreased the cutting force. The minimum quantity lubrication (MQL) method was studied in conjunction with cryogenic machining [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Machining processes with the application of MQL have successfully achieved reductions in tool wear, surface roughness, and improvements in dimensional accuracy [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Suhaimi et al. [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] applied MQL to the indirect cryogenic machining of a titanium alloy, which significantly reduced the cutting forces and tool wear compared to other cryogenic machining technologies that use an internal system and an external nozzle. Zou et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] demonstrated that the application of MQL during cryogenic machining was effective in reducing tool wear and surface roughness. However, most previous studies have been performed using relatively short machining times and distances; thus, research on cryogenic machining characteristics under extremely long machining distances is insufficient. Machining is a long-term process in the manufacture of various industrial parts. Therefore, it is necessary to analyze the effects of cooling and lubrication on tribological behavior and machinability based on the removal of a large volume of material. Numerical studies must also be conducted to obtain a clear understanding of the machining characteristics.\u003c/p\u003e \u003cp\u003eIn this study, a cryogenic milling experiment was performed on a Ti alloy (Ti-6Al-4V) over a long machining distance. LN\u003csub\u003e2\u003c/sub\u003e was sprayed using an indirect system and MQL was applied by spraying lubricants through an external nozzle. The cutting force and tool wear length were determined based on the machining distance. The effects of cryogenic cooling and lubrication on machinability were identified based on experimental data. The effects were further analyzed using numerical simulations, and the tool temperature was predicted. The machining characteristics were thoroughly investigated based on the simulation results.\u003c/p\u003e"},{"header":"2. Experimental setup","content":"\u003cp\u003eA cryogenic milling experiment was performed using an indirect spraying system, in which LN\u003csub\u003e2\u003c/sub\u003e was used as the cryogenic coolant. A tungsten carbide tool was used, and channels for LN\u003csub\u003e2\u003c/sub\u003e were formed inside a commercial milling tool (F1200, Walter) for the indirect system. The coolant circulating inside the cutting tool was sprayed outward through holes at a distance from the tool tip. The shape of the cutting tool is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The MQL method was also applied to enhance the frictional characteristics of the cutting tool surface [cryoMQL (cryogenic\u0026thinsp;+\u0026thinsp;MQL)]. A vegetable-oil-based lubricant was sprayed with the external nozzle directed toward the tool tip. The coolant and lubricant flow rates were controlled at pressures of 4 and 7 bar, respectively. The target work material was Ti-6Al-4V. A 100 mm \u0026times; 100 mm \u0026times; 100 mm block-type specimen was manufactured and cut using side-down milling. A machining center (HTC-1000, HANKUK) was designed to spray the coolant and lubricant stably. The machine passed through the spindle for LN\u003csub\u003e2\u003c/sub\u003e and a system that controlled the coolant and lubricant pressures. The experimental setup is illustrated in Fig.\u0026nbsp;2(a).\u003c/p\u003e \u003cp\u003eThe experiments were conducted over excessively long machining distances. Machining distances of up to 400 passes were applied; a machining distance of 100 mm was defined as one pass. Considering the specimen size, the machining paths shown in Fig.\u0026nbsp;2(b) were applied. A feed time was available between one pass and the next because the cutting tool moved to the starting point of the next pass after machining in the previous pass. The feed time was relatively long for 100, 200, and 300 passes owing to the long feed distance. The cutting force was measured during the machining. A force dynamometer (9139AA, Kistler) was attached to the working material. The tool wear was investigated after 400 machining passes. The tool flank wear length was measured using a microscope (Z16APO, Leica). A cutting speed of 90 m/min, an axial depth of 5 mm, and a radial depth of 1 mm were used. Two feeds (0.07 and 0.08 mm/tooth) were adopted. The experimental conditions are listed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. For comparative analysis, wet machining was also performed, and the effects of cryogenic cooling and lubrication on tribological behavior (frictional characteristic on tool surface) and machinability were investigated based on the cutting force and tool wear.\u003c/p\u003e\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eExperimental condition of end milling\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWork material\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCooling condition\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTool diameter (mm)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCutting speed\u003c/p\u003e\n \u003cp\u003e(m/min)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadial depth\u003c/p\u003e\n \u003cp\u003e(mm)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAxial Depth\u003c/p\u003e\n \u003cp\u003e(mm)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eFeed\u003c/p\u003e\n \u003cp\u003e(mm/\u003c/p\u003e\n \u003cp\u003etooth)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMachining\u003c/p\u003e\n \u003cp\u003edistance\u003c/p\u003e\n \u003cp\u003e(pass)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eTi-6Al-4V\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eWet\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" rowspan=\"2\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" rowspan=\"2\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" rowspan=\"2\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" rowspan=\"2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e1\u0026ndash;400\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCryoMQL\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n"},{"header":"3. Numerical modeling","content":"\u003cp\u003eFinite element simulation was conducted using DEFORM software to numerically study the cryogenic milling characteristics. DEFORM is a specialized simulation software for manufacturing processes, particularly machining, and includes a machining module that can simulate various machining operations [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. A milling module was used in this study. A milling tool with the same shape as that used in the experiment was used. Certain parts of the work material, near the cutting area, were implemented. The mesh was generated using the DEFORM automatic mesh-generation method with a minimum element size of 0.042 mm. The positions of the work material elements farthest from the cutting edge were fixed. Under the wet condition, the initial temperatures of all the elements were set at room temperature (25 ℃). Conversely, under the cryoMQL condition, a cryogenic temperature of -176 ℃ was applied to the cutting tool, because the internal circulation of LN\u003csub\u003e2\u003c/sub\u003e lowered the cutting tool temperature to a level similar to that of LN\u003csub\u003e2\u003c/sub\u003e. The cryogenic temperature was determined by measuring the temperature of the sprayed LN\u003csub\u003e2\u003c/sub\u003e. The model setup is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The mechanical and thermal properties of Ti-6Al-4V and tungsten carbide embedded in the software were applied to the cutting tool and work material. Machining was simulated by rotating the cutting tool, and the cutting force and tool temperature were predicted. The cutting force and temperature were closely correlated. In machining, the plastic deformation of the material generates plastic stress and a cutting force, which determine the heat generated at the shear plane and is the main source of the cutting temperature. Therefore, tool temperature was predicted under a simulated cutting force that matched the experimental results. The numerical study followed the flowchart shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"4. Result and discussion","content":"\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e4.1 Experimental cutting force and tribological behavior\u003c/h2\u003e \u003cp\u003eThe cutting forces were measured in real-time during cryogenic milling. The resultant forces were obtained from data measured in the x-, y-, and z-directions. The experimental results at each pass were derived via root mean square (RMS) analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e5\u003c/span\u003e). In machining, the cutting force can be affected by various factors such as the work material temperature, cutting temperature, and tool wear. An increase in temperature during machining can lower the cutting force by weakening the work material. The evolution of tool wear can cause a geometrical deformation of the cutting tool, thereby increasing the cutting force. The measurement data were analyzed by considering these phenomena.\u003c/p\u003e \u003cp\u003eThe analysis was performed at a feed rate of 0.07 mm/tooth. Under wet conditions, the cutting force increased rapidly as the machining distance increased to 20 passes. In titanium machining, which generates high temperatures, the length of flank wear can rapidly increase at the start of machining. Thus, the increase in cutting force at short machining distances appears to be caused by tool wear. After 20 passes, the rate of increase in the cutting force decreased. However, abrupt changes were observed at certain machining distances (100, 200, and 300 passes), and the force initially increased and then decreased significantly. The feed time for the next machining process was relatively long at 100, 200, and 300 passes, and the tool temperature that was increased by machining decreased. The mechanical properties of the tool could become unstable owing to the large temperature change, and the impact of contact between the tool and work material when machining was restarted may have induced tool deformation. The deformed tool geometry presumably caused sudden increases and decreases in the cutting force. However, under the cryoMQL conditions, there was no significant increase in the cutting force during machining for up to 100 passes. The cutting force slightly increased at short machining distances, but immediately decreased and remained low until 100 passes. Under these conditions, the cutting tool was cooled using LN\u003csub\u003e2\u003c/sub\u003e and the tool surface was lubricated. The decreased cutting temperature slowed the evolution of the tool wear and prevented an increase in the cutting force. Then, the minimum quantity lubricant in contact with the tool surface reduced surface friction, so the adequate lubrication enhanced the tribological performance, lowering cutting force. Abrupt changes in the cutting force were observed at 100 and 300 passes, similar to the wet conditions; the long feed time and reduced tool temperature were considered to be the causes. Regardless, the overall cutting force was less than that under wet conditions. Therefore, the simultaneous application of cryogenic cooling and MQL was suitable for reducing the cutting force. To compare the cutting forces based on cooling conditions, the cutting forces at different machining distances (1, 100, 200, 300, and 400 passes) were observed (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e6\u003c/span\u003e). CryoMQL reduced the cutting force by up to 17.7% after 100 passes. Under both cooling conditions, the cutting force tended to increase with the machining distance. Increased tool wear may have induced this phenomenon because tool wear is proportional to the machining distance.\u003c/p\u003e \u003cp\u003eAt a feed rate of 0.08 mm/tooth, the cutting forces increased under both cooling conditions compared to that for a feed rate of 0.07 mm/tooth. An increase in feed rate indicates an increase in machining area. An enlarged machining area generates a large cutting force. Under wet conditions, the trend of the cutting force according to the machining distance was the same as that at a feed rate of 0.07 mm/tooth, but the range over which the cutting force fluctuated, increased. A large cutting force can increase the tool vibration, which affects the cutting force and causes force fluctuations. Under the cryoMQL conditions, the cutting force appeared irregular, and its tendency based on the machining distance was insignificant. The increased magnitude of cutting force may have contributed to this phenomenon. Generally, because MQL has a better lubrication effect than emerging floods under wet conditions, it can prevent an increase in the cutting force. However, the cutting temperature was reduced by the LN\u003csub\u003e2\u003c/sub\u003e which was sprayed, and the low temperature and change in the feed rate significantly improved the cutting force. The lubricant was not sufficient to reduce the cutting force, and the corresponding phenomena induced extreme tool vibrations with irregular fluctuations in the force. Consequently, the difference between the cutting forces under the wet and cryoMQL conditions was not large. Thus, the cooling and lubrication environments must be determined depending on the machining conditions, and the cryoMQL condition was considered to have a remarkable effect on the cutting force reduction at feed rates of less than 0.08 mm/tooth.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e4.2 Experimental tool wear\u003c/h2\u003e \u003cp\u003eThe faces of the tool flank under all cooling and machining conditions were captured after completion of machining at a distance of 400 passes (Fig.\u0026nbsp;7). Flank wear was observed under all conditions. The heat and stress generated continuously during machining can induce wear. Chipping was observed under all conditions except for the cryoMQL with a feed rate of 0.07 mm/tooth. Side-down milling is a process in which a tool is affected during each rotation. When a tool rotates and enters the work material, a large cutting force is generated when it encounters a large machining area. This can result in tool breakage under wet conditions. Furthermore, the tool temperature may fluctuate owing to heat from machining and cooling owing to coolants. The tool can undergo thermal shock due to a sudden change in temperature, leading to chipping. Conversely, no chipping was observed under the cryoMQL condition with a feed rate of 0.07 mm/tooth, where a lubricant was sprayed to reduce friction; this is an important factor for determining the frictional heat on the surface. MQL prevents thermal shock by decreasing the frictional heat, and cryogenic cooling can reduce the cutting temperature. Thus, the synergistic effect of LN\u003csub\u003e2\u003c/sub\u003e and the lubricant maintained a low tool temperature without an abrupt increase in the cutting temperature, and the reduced temperature fluctuation prevented chipping. However, this result was only applicable at a feed rate of 0.07 mm/tooth; chipping was observed at 0.08 mm/tooth. The probability of tool breakage increases when a large cutting force was applied at extremely low temperatures. To understand this phenomenon, the relationship between a large cutting force and a low tool temperature must be studied. This case is discussed detail in a numerical study of the tool temperature.\u003c/p\u003e \u003cp\u003eFlank wear lengths were measured from the captured flank faces. Under each condition, five points were selected at equal intervals on the tool edge, and the average value of the five wear lengths was used for the comparative analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e8\u003c/span\u003e). The flank wear lengths under cryo-MQL conditions were shorter than those under wet conditions. Under cryoMQL conditions, the tool temperature decreased, delaying the evolution of wear. Because heat was applied to the cutting tool for an extended time owing to the long machining distance, the influence of the cooling conditions became evident. In particular, the minimum wear length was observed at a feed rate of 0.07 mm/tooth; the wear length under cryoMQL conditions was 46.4% less than that under wet conditions. Under these conditions, the cutting force was relatively small, which could induce a small stress and have a major effect on tool wear. Tool damage decreased when the cutting force was relatively small. Based on these results, the cryoMQL condition was considered effective in improving machinability in terms of tool wear.\u003c/p\u003e \n\u003ch2\u003e4.3 Numerical cutting force and tribological behavior\u003c/h2\u003e\n\u003cp\u003eThe cutting forces under wet and cryoMQL conditions were predicted using numerical simulations. During milling, the cutting force varies depending on the tool rotation angle and machining area. In down milling, the cutting force rapidly increased at the beginning of machining and then decreased as the tool rotates. To understand machining characteristics, the profile and maximum values of the resultant force were predicted, and the maximum resultant force for each condition was used as the simulation result. The machining conditions, which included a cutting speed of 90 m/min and a feed rate of 0.07 mm/tooth was applied. The numerical study focused on the effect of the cooling conditions, excluding the influence of wear. Thus, a sharp tool edge without wear was adopted, indicating that a machining distance of one pass was considered. The chip formation and strain obtained from the machining simulations are shown in Fig. 9. The experimental cutting force measured in one pass was used for validation, and the simulation results are shown in Fig. \u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e. Under cryo-MQL conditions, the cutting force was lower than that under wet conditions. When the temperature of the tool surface was decreased by LN\u003csub\u003e2\u003c/sub\u003e, the surface adhesion decreased, which decreased the adhesive friction and frictional force on the tool surface. A change in frictional characteristics induced a decrease in the cutting force. The same result was observed in the experimental data; the maximum resultant force under the cryoMQL condition reduced by 6.1% compared to that under wet conditions. The decrease in tool temperature and the effect of MQL spraying effectively reduced the tool surface friction. It is difficult for an emerging flood to flow into the tool-chip interface under wet conditions; therefore, the effect of the MQL was apparently greater. A decrease in friction directly reduces frictional heat and delays tool wear. Thus, the improved adhesive friction reduced the cutting forces not only at one pass, but also at long machining distances, as indicated by the experimental data.\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e4.4 Numerical tool temperature\u003c/h2\u003e\n \u003cp\u003eThe tool temperature was simulated during the side-down milling. A cutting speed of 90 m/min, a feed rate of 0.07 mm/tooth, and a machining distance of 1 pass were applied. Various factors generate heat during the machining process. Plastic deformation of the work materials increases the shear temperature, and the adhesive friction on the tool surface generates frictional heat; the sprayed LN\u003csub\u003e2\u003c/sub\u003e induces cryogenic heat. The heat applied to the cutting tool was predicted by considering the plastic stress in the shear zone and thermal properties of the cutting tool and work material. The plastic stress in titanium machining was simulated and considered. The temperature variation was visualized in the tool geometry, as shown in Fig. 11. The temperature varied depending on the position on the tool edge, and a large temperature increase was observed in the area near the tool tip and at a certain distance from the tip. During the milling process, the tool tip first made contact with the work material over a small machining area, generating high stress and resulting in a high temperature. Subsequently, chips were formed during the machining of the slides onto the tool surface. Frictional heat was generated by tool surface friction and sliding chips at a certain distance from the tool tip, as demonstrated by tool wear measurement results. When the faces of the tool flank were examined, chipping was observed in the middle of the tool edge, which is a region similar in location to where the temperature significantly increased in the simulation. Therefore, chipping can occur under the influence of increased temperatures. The maximum temperatures on the tool edge for each condition were compared to quantitatively analyze the effect of the cooling conditions (Fig. \u003cspan class=\"InternalRef\"\u003e12\u003c/span\u003e). Under the cryoMQL condition, a lower maximum temperature was confirmed compared to the wet condition; the temperature in Kelvin was reduced by 46.5%, and subzero temperature in degrees Celsius, was observed. Cryogenic cooling may have caused this decrease by reducing the initial tool temperature and heat generated. Regarding the measured tool wear, the cryoMQL condition with a feed rate of 0.07 mm/tooth minimized the flank wear length without chipping. Low temperatures improve the resistance to tool wear. The sprayed LN\u003csub\u003e2\u003c/sub\u003e maintained the cutting tool temperature continuously, thereby reducing the possibility of tool failure. Conversely, when a 0.08 mm/tooth feed rate was applied, chipping was observed to be the same as in the wet condition. Generally, the brittleness of a material increases as the temperature decreases, and brittle materials break under large forces. A cryogenically cooled cutting tool is relatively brittle and is exposed to a greater risk of breakage owing to the large feed rate, causing a large cutting force. Thus, applying a feed rate of 0.08 mm/tooth may have caused chipping despite the cryoMQL condition. Nevertheless, because tool wear tended to decrease under cryoMQL conditions, the temperature reduction enhanced machinability.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe effects of cryogenic cooling and MQL were studied experimentally and numerically during side-down milling using long machining distances. The cutting force, tool wear, and tool temperature were analyzed. The findings are summarized as follows.\u003c/p\u003e \u003cp\u003e(1) The cryoMQL condition reduced the cutting force. The tool surface friction was reduced by decreasing the surface temperature and lubrication using MQL. Cryogenic cooling slowed the evolution of tool wear, preventing an increase in the cutting force owing to an increase in the machining distance. When a 0.07 mm/tooth feed rate was applied, the cutting force was reduced by up to 17.7% compared to the wet condition.\u003c/p\u003e \u003cp\u003e(2) The cryoMQL condition with a low feed rate (0.07 mm/tooth) increased the resistance to chipping of the cutting tool. Continuous cooling by spraying LN\u003csub\u003e2\u003c/sub\u003e and low-friction heat reduced the possibility of thermal shock.\u003c/p\u003e \u003cp\u003e(3) The simultaneous use of cryogenic cooling and MQL decreases the flank wear length. The rate of increase in the tool wear was reduced because the tool temperature was decreased by cryogenic cooling and the reduction in frictional heat. The flank wear length after 400 machining passes was 46.6% shorter than that under wet conditions.\u003c/p\u003e \u003cp\u003e(4) The use of LN\u003csub\u003e2\u003c/sub\u003e and MQL decreased the numerical tool temperature. The maximum temperature on the tool edge was reduced by 46.5% compared with that under wet conditions. The temperature reduction had a remarkable influence on the decrease in cutting force and tool wear.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the Academic Promotion System Tech University of Korea and by research fund of Chungnam National University, and the \u0026quot;Regional Innovation Strategy (RIS)\u0026quot; through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE) (2021RIS-003).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eConflicts of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAuthor information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors and Affiliations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eProf. Do Young Kim., Ph.D\u003c/p\u003e\n\u003cp\u003eDepartment of Mechatronics Engineering, Chungnam National University, Daehak-ro 99, Yuseong-gu, Daejeon, Republic of Korea, 34134\u003c/p\u003e\n\n\u003cp\u003eJu-Hyung Ha., Master Degree\u003c/p\u003e\n\u003cp\u003eWorkerInSpace Inc., R\u0026amp;D Center, Jiphyeonjungang 2-ro, Republic of Korea, 30141\u003c/p\u003e\n\n\u003cp\u003eMin Gi Ha., M.S. course\u003c/p\u003e\n\u003cp\u003eDepartment of Mechanical Convergence Engineering, Kyungnam University,\u003cbr\u003e\u0026nbsp;Kyungnamdaehak-ro 7, Masanhappo-gu, Changwon-si, Gyeongsangnam-do, Republic of Korea, 51767\u003c/p\u003e\n\n\u003cp\u003eProf. Dong Min Kim. Ph.D\u003c/p\u003e\n\u003cp\u003eDepartment of Mechanical Design Engineering, Tech University of Korea,\u003cbr\u003e\u0026nbsp;237 Sangidaehak-ro, Siheung-si, Gyeonggi-do, Republic of Korea, 15073\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eContributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDongmin Kim was responsible for the study\u0026rsquo;s conception and design. Ju-Hyung Ha prepared the experiments and collected the data, while Doyoung Kim carried out the data analysis and wrote the initial draft of the manuscript. Min Gi Ha supported data analysis with Doyoung Kim on earlier versions. All authors reviewed and approved the final manuscript.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCorresponding author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCorrespondence to Dongmin Kim\u003c/p\u003e\n\n\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eC. Castellani, R.A. Lindtner, P. Hausbrandt, E. Tschegg, S.E. Stanzl-Tschegg, G. Zanoni, S. Beck, A.M. Weinberg, Bone\u0026ndash;implant interface strength and osseointegration: biodegradable magnesium alloy versus standard titanium control. Acta Biomater. 7 (2011) 432\u0026ndash;440. https://doi.org/10.1016/j.actbio.2010.08.020.\u003c/li\u003e\n\u003cli\u003eM. Long, H.J. Rack, Titanium alloys in total joint replacement\u0026mdash;a materials science perspective. Biomaterials. 19 (1998) 1621\u0026ndash;1639. https://doi.org/10.1016/s0142-9612(97)00146-4.\u003c/li\u003e\n\u003cli\u003eN. Li, Y. Chen, D. Kong, Wear mechanism analysis and its effects on the cutting performance of PCBN Inserts during turning of hardened 42CrMo. Int. J. Precis. Eng. Manuf. 19 (2018) 1355\u0026ndash;1368. https://doi.org/10.1007/s12541-018-0160-6.\u003c/li\u003e\n\u003cli\u003eS.K. Choudhury, G. Bartarya, Role of temperature and surface finish in predicting tool wear using neural network and design of experiments. Int. J. Mach. Tool. 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Nalbant, A review of cryogenic cooling in machining processes. Int. J. Mach. Tool. Manuf. 48 (2008) 947\u0026ndash;964. https://doi.org/10.1016/j.ijmachtools.2008.01.008.\u003c/li\u003e\n\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":true,"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":"Cryogenic machining, Minimum quantity lubrication, Titanium alloy, Cutting force, Tool wear","lastPublishedDoi":"10.21203/rs.3.rs-5817747/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5817747/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eCryogenic machining involves spraying cryogenic coolants to reduce the cutting tool temperature. In this study, cryogenic machining was applied to a titanium alloy with minimum quantity lubrication (MQL), and the tribological and machining performance were evaluated. As side-down milling was performed, the effects of cryogenic cooling and MQL were experimentally and numerically investigated with long machining distances (40, 000 mm), and the cutting force, tool wear, and tool temperature were analyzed. Compared to the wet condition, under the cryoMQL condition, which represents the simultaneous application of cryogenic cooling and MQL, the cutting force and flank wear length decreased by up to 17.7% and 46.4%, respectively. The cryogenically cooled and lubricated cutting tool enhanced the tribological performance, slowing tool wear. The reduced surface friction of the tool and tool wear decreased the frictional force and changed the trend of the cutting force according to the machining distance. The cryoMQL milling was simulated using DEFORM software. In the numerical study, a decrease in the tool temperature, which affects the reduction in cutting force and tool wear, was observed under cryoMQL conditions. The maximum tool temperature was reduced by 46.5% compared with that under wet conditions.\u003c/p\u003e","manuscriptTitle":"Experimental and numerical study on tribological behavior and machinability in titanium indirect cryogenic machining with minimum quantity lubrication","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-23 16:11:55","doi":"10.21203/rs.3.rs-5817747/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revisions Needed","date":"2025-03-19T18:34:07+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2025-01-21T20:41:45+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-01-21T19:53:59+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-01-20T02:50:07+00:00","index":"","fulltext":""},{"type":"submitted","content":"The International Journal of Advanced Manufacturing Technology","date":"2025-01-16T23:35:01+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":"8f103c7f-a38e-491f-9b2f-0452c455e75c","owner":[],"postedDate":"January 23rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-06-09T15:59:27+00:00","versionOfRecord":{"articleIdentity":"rs-5817747","link":"https://doi.org/10.1007/s00170-025-15774-7","journal":{"identity":"the-international-journal-of-advanced-manufacturing-technology","isVorOnly":false,"title":"The International Journal of Advanced Manufacturing Technology"},"publishedOn":"2025-06-03 15:57:05","publishedOnDateReadable":"June 3rd, 2025"},"versionCreatedAt":"2025-01-23 16:11:55","video":"","vorDoi":"10.1007/s00170-025-15774-7","vorDoiUrl":"https://doi.org/10.1007/s00170-025-15774-7","workflowStages":[]},"version":"v1","identity":"rs-5817747","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5817747","identity":"rs-5817747","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}