Feasibility study of a bi-materials magnetic laminate FeSi6.5/ceramic using powder bed fusion additive manufacturing

Feasibility study of a bi-materials magnetic laminate FeSi6.5/ceramic using powder bed fusion additive manufacturing | 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 Feasibility study of a bi-materials magnetic laminate FeSi6.5/ceramic using powder bed fusion additive manufacturing Mohamed Arezki AMITOUCHE, Olivier Marconot, Yoann Donlos, Alejandro Ospina, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6498025/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The ferromagnetic material FeSi6.5 exhibits lower magnetic losses compared to the more widely used FeSi3, commonly employed in the production of laminated sheets for stators and rotors. This makes FeSi6.5 a promising candidate for electric motor manufacturing. However, its high silicon content complicates significantly production through conventional lamination processes. Additive manufacturing emerges as a viable alternative for this application. In electric motors, laminated sheets are separated by insulating layers to reduce eddy current losses. While additive manufacturing allows the fabrication of complex shapes, it is currently limited to single-material structures and cannot replicate the laminated architecture of electric motors. Research on multi-material additive manufacturing remains in its early stages of development. The challenge is to manufacture laminated electric motors using additive manufacturing, with thin ceramic insulating layers and ferromagnetic FeSi6.5 material layers. To achieve this, we have developed an innovative system to modify our LPBF manufacturing machine to work with two materials. This paper presents our work on the modification of our LPBF machine for the bi-material process, as well the ceramic/metal interface optimization. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 1. Introduction Electric machines (EM) are indispensable in modern industry, with diverse applications ranging from domestic uses to propulsion and electricity generation. They generate the world's electrical energy through electromechanical conversion. Given their growing importance, scientific research is constantly striving to improve their performance. For optimal energy conversion, it is essential to design innovative, high-performing, and cost-effective motors. The efficiency, durability, and cost of EMs depend heavily on the materials used. Soft magnetic materials play a key role for the stators. Their improvement is essential to increase machine performance, reducing energy losses and production costs. [1] [2]. Several innovative manufacturing techniques are used to produce these soft magnetic materials intended for electric machines. These technologies are specifically designed to address the challenges associated with their processing, which is often complex using conventional manufacturing methods. Among these advanced approaches, additive manufacturing stands out as a promising solution, offering greater flexibility and enhanced performance. Additive manufacturing of ferromagnetic materials presents a remarkable and evolving potential to improve both mechanical and magnetic properties. Among soft ferromagnetic alloys (FeSi, FeNi, FeCo, etc.), FeSi alloys, also known as ferromagnetic silicon steel, are the most widely used due to their optimal magnetic properties, including low coercivity (Hc = [50–100 A/m]), high magnetic flux density (Bs = [1,6–1,8 T]) and high relative permeability (µr = [10 000–12 000]). [3] [4] Within the FeSi steel family, the 6.5%wt silicon alloy stands out for its high potential for applications in magnetic devices, this is due to its high electrical resistivity, which permits to decrease significantly Eddy Current losses for AC application, virtually zero magnetostriction and low magnetocrystalline anisotropy, making it a particularly suitable material for applications. [3] [4] [5], The inherent brittleness of high-silicon steels (> 3% wt Si) limits their manufacturing options. Additive manufacturing provides a versatile solution, allowing the production of these alloys with enhanced magnetic properties. [2] [4] [6]. Electric machines are designed with thin laminated sheets, separated by insulating layers, to effectively disrupt unwanted currents and reduce magnetic losses caused by eddy currents. However, while additive manufacturing enables the production of monolithic components with complex geometries, it does not allow for the integration of the lamination process used in electric motors. This limitation presents a major challenge in controlling eddy current losses, requiring solutions to optimize magnetic performance.[7] [8] Additive manufacturing creates new possibilities for producing intricate composites, particularly by alternately stacking insulating ceramic layers with magnetic metal layers. However, this configuration has been scarcely explored in the literature, and previous efforts have not yielded a fully satisfactory final stacking [2] [9] Our research marks a significant step forward in investigating the potential of layering ferromagnetic and ceramic materials, an approach that holds promise for improving the properties of electrical steels. This technology is essential for the advancement of electrical devices such as sensors, actuators, and heating elements. Nevertheless, although several commercial additive manufacturing systems exist, only a few are well-suited for multi-material production, making this a continuously evolving field.[10] The fabrication of functionally graded structures combining ceramics and steel necessitates the selection of a ceramic material with a coefficient of thermal expansion (CTE) closely matching that of steel. Zirconia (ZrO₂) is particularly well-suited for this purpose due to its thermal and mechanical compatibility with steel [11] [12]. The CTE of steel ranges between (11 × 10⁻⁶ to 13 × 10⁻⁶ K⁻¹)[13], while zirconia exhibits a CTE of 7.5 × 10⁻⁶ K⁻¹ at 20°C and 15.3 × 10⁻⁶ K⁻¹ at 1000°C [14], making it a viable candidate for integration with metallic phases. Experimental studies have demonstrated that zirconia-based materials can be successfully processed via selective laser melting (SLM) without the necessity for preheating .[11] [14] [9]. Pure zirconia is often referred to as "ceramic steel" due to its outstanding mechanical properties, including high fracture toughness and wear resistance. It exists in three primary crystallographic phases: monoclinic at low temperatures, tetragonal above 1170°C, and cubic beyond 2370°C. The transformation from the tetragonal to the monoclinic phase induces a volumetric expansion of approximately 3–4%, which can lead to crack formation. To mitigate this issue, the incorporation of stabilizers such as yttrium oxide (Y₂O₃) enables the retention of the tetragonal phase at room temperature, thereby preventing phase transformation-induced damage. [11] [15] Despite its advantageous properties, zirconia poses significant challenges in additive manufacturing due to its high melting point and low absorption of laser energy [11] [16] H. Hayashi and al. [15] measured the CTE of yttria-stabilized zirconia (YSZ) with varying Y₂O₃ content (3, 6, 8, and 10 mol%), reporting average CTE values of 10.8 × 10⁻⁶ K⁻¹ and 10.1 × 10⁻⁶ K⁻¹ for 3 mol% and 8 mol% YSZ, respectively, over the temperature range of 298 K to 873 K. Additionally, Liu et al. [11] demonstrated that employing a secondary laser to preheat the powder bed prior to deposition significantly reduces cracking and defect formation in partially stabilized zirconia (YSZ). Preheating temperatures in the range of 1500°C to 2500°C have been found to effectively minimize residual thermal stresses and solidification-induced cracking. However, this approach remains technically challenging, resource-intensive, and is constrained to localized heating areas, limiting its industrial scalability. In this study, we have modified our laser powder bed fusion (LPBF) system, originally designed for single-material fabrication in a monolithic block, to enable the production of laminated materials. The primary objective is to alternate layers of ceramic and ferromagnetic FeSi6.5. Initially, we characterized the powders used for both materials, FeSi6.5 and ZrO₂-Y₂O₃, defining their essential properties to ensure optimal compatibility with the LPBF process. Subsequently, we detail the modifications implemented to facilitate multi-material fabrication. In the second phase, we optimize the processing parameters for each material individually to establish suitable manufacturing conditions. Following this, we develop and apply a deposition protocol for ZrO₂-Y₂O₃ ceramic onto ferromagnetic FeSi6.5, considering the thermal and physicochemical interactions between the two materials. Finally, in the results section, we present the fabrication outcomes for each material independently, followed by the results of the laminated composite structure. The study concludes with a comprehensive analysis of the findings, addressing the challenges encountered and the advancements achieved in the process. 2. Materials and procedures 2.1. Powder characterization: The characteristics of the powder play a crucial role in additive manufacturing, directly influencing process parameters and the final properties of the material. In this study, the raw material used is an atomized ferromagnetic silicon steel powder containing approximately 6.5 wt% Si. This powder was internally produced using UTBM’s atomizer. To enhance adhesion and flowability, it was dried at 80°C for 30 minutes. The particle size distribution ranges from 15 to 45 µm (D15 – D45) Fig. 1 a. A sieving process was performed to refine this distribution by removing particles larger than 63 µm. From a morphological perspective, the powder consists predominantly of spherical or quasi-spherical particles, which are characteristic of atomized powders. However, a smaller proportion of irregularly shaped particles is also present. This morphology results from the rapid solidification occurring during atomization. The particle surfaces are generally smooth, with occasional slight irregularities likely caused by splattering or partial coalescence of droplets during cooling Fig. 1 b. These characteristics directly influence the physical properties of the powder, including its flowability, packing density, and reactivity. As a result, this powder is particularly well-suited for applications in powder metallurgy, where a controlled particle size distribution is essential to ensure optimal performance in additive manufacturing. Three ceramic compositions were evaluated in this study: ZrO₂-SiO₂ (33%), Al₂O₃-SiO₂ (24%), and ZrO₂-Y₂O₃ (7%). The objective was twofold: to assess the feasibility of fabricating these ceramics and to investigate their deposition on an FeSi6.5 substrate. Fabrication and deposition tests were conducted for each of the three compositions. Following these tests, ZrO₂-Y₂O₃ ceramic was selected for further studies. The ZrO₂-Y₂O₃ powder with 7% by weight of Y₂O₃ and particle size distribution between 15 and 45 µm (D22 - D45) Fig. 2 (a). To improve the homogeneity of the powder, sieving was performed to remove particles larger than 63 µm. SEM analysis of ZrO₂-Y₂O₃ powder reveals a morphology mainly composed of spherical and quasi-spherical particles Fig. 2 b. The particles exhibit relatively smooth surfaces and uniform dimensions, characteristics sought to ensure optimal packing density and good flowability, which are essential in additive manufacturing or sintering processes. Table.1 presents a detailed analysis of the characteristics of FeSi and YSZ powders, comparing the compositions provided by producers with those obtained by Scanning Electron Microscopy (SEM). For FeSi, the composition is 6.4% silicon and 93.6% iron, while the SEM analysis reveals 6.2% Si and 95.35% Fe. For YSZ, the theoretical composition is 93% ZrO₂ and 7% Y₂O₃, whereas the SEM analysis shows 7.9% yttrium and 92.1% zirconium. The particle sizes for both powders range between 15 and 45 µm. Table.1.Characteristics of FeSi6.5 and ZrO₂-Y₂O₃ Powders: Composition and Particle Size Type Powder Commercial Name Powder Manufacturer Manufacturer's Composition SEM Composition Size (µm) Soft Magnetic FeSi6.5 UTBM Fe 6.5% Si 6,4% Si − 93.6% Fe 15–45 ceramic YSZ H.C.Starck 93% ZrO 2 7% Y₂O₃ 7.9% Y₂O₃ − 92.1% ZrO 2 15–45 2.2. Manufacturing process : The experiments were carried out in a specific selective laser melting machine developed at the ICB-PMDM laboratory. A Realizer SLM250 machine. An Ytterbium fiber laser source with a maximum theoretical power output of 120 W and a wavelength of 1064 µm was used. The laser focus beam has a diameter of 34 µm. The building chamber dimension is 25 × 25 × 25 cm. The machine was filled with a shielding gas during all experiments to remove smoke and maintain a stable pressure. The chamber was purged of residual oxygen below 0.1% to avoid oxidation. The laser scanning mode was continuous. However, the laser displacement was driven by two mirrors fixed on a stepper motor to insure X and Y directions, with a galvanometric head. A continuous weld bead was formed point by point, with a distance Pdist between each point. The laser remained at each point for an exposure time of Texpo and then moves to the next point at the Pdist distance along the trajectory. Thus, Pdist and Texpo determine the effective scanning speed Fig. 4 . The system developed for integration into the LPBF machine consists of a powder distributor with two separate powder feeders, allowing the manufacturing machine to be fed with one or two powders Fig. 3 a. This distributor operates with argon gas, which pushes the powder through a pipe into the build chamber. This system allows switching from one powder to another or simultaneous feeding with both. For spreading powder on the build bed, two powder inlet chambers are integrated into the coater. These two chambers are separate, and each chamber contains different materials. 2.3. Experimental process : Figure 4 illustrates the adopted laser scanning strategy and the main variables influencing the fabrication of the samples. The deposition process consists of superimposing successive layers of material using a laser, with precise control over two key parameters: laser power (P) and scanning speed (V). Each laser pass generates a track of width h, defining the geometry of the deposited layer. A specific scanning strategy has been implemented to ensure homogeneous construction and minimize residual stresses. This strategy is based on a 90° rotation of the laser beam orientation between successive layers. Thus: In the XY plane, which corresponds to the laser scanning plane and is perpendicular to the build direction, the material tracks are deposited in an alternating pattern between each layer. The XZ and YZ planes represent the side views parallel to the build direction, allowing for an analysis of the structure's evolution as layers are progressively deposited. This alternating scanning orientation between layers enhances thermal distribution, reduces the risk of distortion, and promotes uniform adhesion between layer critical factors in achieving a high-quality final part. In this work, we use the volumetric energy equation, which represents the main manufacturing parameters. The volume energy density (VED)(J/mm³), corresponds to the energy density applied to a given volume and depends on several parameters: the laser power P (W); the laser scanning speed v (mm/s); the hatch distance h (mm), defining the distance between the lines traced by the laser beam; and t, the layer thickness (mm), corresponding to the thickness of the deposited powder bed Eq. 1. $$\:VED=\frac{p}{vht},\:\:v=\frac{p}{Eht}\:\:\:\:\:\:\:\:\:\:\:\left(1\right)$$ a) Monomaterial additive manufacturing : In order to optimize the manufacturing parameters of FeSi6.5 and achieve a higher density, an initial test plan was conducted. During this phase, 25 samples were fabricated with laser power between 73 W and 95 W and scanning speed between 0.34 m/s and 0.52 m/s. Surface density was assessed using image analysis. Among the different tested combinations, three power/speed pairs were selected for further investigation due to their higher density: 83 W, 88 W, and 95 W, with a speed of 0.41 m/s. In the second campaign, the speed was fixed at 0.41 m/s, and the power was maintained at the three previously selected values (83 W, 88 W, and 95 W). The distance between laser tracks (hd) was varied (20, 30, and 40 µm) to optimize track overlap and sample density. Results showed that a distance of 30 µm provided the highest densities. Finally, in the third plan, the distance between laser points (pdistance) was varied to increase energy density. The distance between tracks (hdistance) was fixed at 30 µm, the speed at 0.41 m/s, and the power was varied as before. The calculated exposure times, using Eq. 2, were 60, 80, and 100 µs. The optimal parameters determined from these three experimental campaigns are presented in Table.2 Liu et al [11], have shown that the fabrication of a YSZ ceramic on a ceramic substrate of the same material is possible. In our procedure, we chose to fabricate YSZ samples on a stainless-steel substrate because it is closer to the characteristics of FeSi6.5 and thus anticipate adhesion challenges. Various manufacturing parameters were studied to determine the optimal conditions for achieving the highest relative density. To this end, we maintained a constant layer thickness of 30 µm, the minimum achievable with our equipment, to approximate the thin insulating layers used in electric motors. The apparent relative density was determined by optical microscopy. In a first series of experiments, we varied the volumetric energy density from 133 to 253 J/mm³, in steps of 30 J/mm³. These values correspond to powers of 33 and 73 W, with an increment of 10 W. A total of 25 tests were conducted. Velocities were calculated using Eq. (1), which relates volumetric energy density, power, and velocity. In a second series of experiments, we increased the volumetric energy density in increments of 100 J/mm³, starting from 303 J/mm³ and reaching 503 J/mm³. Simultaneously, we decreased the power in steps of 5 W, from 13 W to 33 W, to perform 25 tests. Among these results, we selected optimum parameters. To validate this result, we fabricated a sample on a ceramic substrate. All parameters are given in Table.2. Table.2. Operational Parameters of Test Campaigns for Additive Manufacturing of FeSi6.5 and ZrO₂-Y₂O₃ Materials by LPBF Matériel FeSi6.5 ZrO₂-Y₂O₃ 7% Test plan Test plan 1 Test plan 2 Test plan 3 Test plan 1 Test plan 2 Layer thickness, t (µm) 30 30 30 30 Hatch distance, h (µm) 60 20, 30, 40 30 30 Laser power, P (W) 73, 78, 83, 88, 95 83, 88, 95 83, 88, 95 33, 43, 53, 63, 73 13, 18, 23, 27, 33 Scan speed, v (mm/s) 340, 370, 410, 460, 520 410 410 109–457 28–121 P distance P (µm) 60 60 30,40,50 30 volume energy density j/mm³ 78–155 169–386 224–257 133,163,193,223,253 303,353,403,453,503 Substrate Inox Inox Plate temperature 240 240 Atmosphere Argon Argon b) Multi-material additive manufacturing : The objective is to create a FeSi6.5/ceramic/FeSi6.5 laminate. The adhesion of the ceramic layer is a crucial parameter for the laminate's performance. In reference study [9], the number of powder layer remelting passes by laser was varied to improve the adhesion of this ceramic layer. In our work, fifteen FeSi6.5 samples (8×8×2 mm) were fabricated on a stainless steel substrate using optimal parameters. Subsequently, YSZ ceramic layers were deposited on these samples using optimized manufacturing parameters. To improve the adhesion of the layers, we studied the effect of the number of powder layer remelting passes (1, 2, or 3 remelting passes), while maintaining a constant manufacturing platform. At each remelting pass, the laser pass orientation was changed by 90 degrees. Additionally, we investigated the influence of the number of ceramic layers (1 to 5 layers) to determine the maximum thickness that allows obtaining a completely insulating ceramic layer with a less rough surface. Figure 5. 3. Results and discussion 3 .1. Monomaterial additive manufacturing results : For the fabrication results of FeSi6.5, the internal density was measured using Archimedes' principle on samples taken directly from the fabrication platform. After cutting and polishing, surface densities were analyzed using an optical microscope. During the third test campaign, the sample with the highest density was selected under the following conditions: a constant velocity of 0.41 m/s, a fixed laser scan spacing of 30 µm, a laser spot spacing of 30 µm, and a power of 95 W. The apparent surface density, estimated by electron microscopy, was 98.93%, while Archimedes' method yielded an internal density of 97.09%. Figure 6 , Fig. 7 a. The results of the two test campaigns conducted for ZrO₂-Y₂O₃ ceramic show that, during the first series of experiments, the fabrication process was stopped as soon as a completely burned but unfused powder was observed. We found that all the samples subjected to a power of 33 W were the only ones to exhibit partial fusion. Analyzing the results for the five tested energy levels, ranging from 133 to 253 J/mm³, we observed that low energy levels led to incomplete melting, while increasing the energy promoted fusion. This phenomenon can be explained by the refractory nature of our material to light. Indeed, its low thermal conductivity limits its ability to quickly absorb a large amount of energy. However, by using 30 µm layers, the energy can be better distributed, thereby facilitating fusion. Our objective is thus to provide enough energy to reach the high melting point of this material while avoiding local overheating caused by excessive power. Consequently, we designed a new series of experiments by reducing the power and increasing the fabrication energy. In our second test campaign, we observed that power levels of 13 and 18 W were insufficient to melt the powder, regardless of the tested energy levels. In contrast, for power levels of 23, 28, and 33 W, successful melting was achieved, enabling the fabrication of samples at all energy levels. These results allowed us to identify the optimal parameters for achieving the highest density. However, the samples fabricated under these optimal conditions did not exhibit good adhesion to the stainless-steel substrate. The parameters determined for ceramic processing in the remainder of the study are as follows: a relatively low laser power of 33 W, a scanning speed of 72 mm/s, a laser track spacing of 30 µm, and a layer thickness of 30 µm, corresponding to an energy density of 503 J/mm³. Figure 7 .b. 3.2. Multi-material additive manufacturing results : During the fabrication of YSZ ceramics on stainless steel substrates, poor adhesion of the ceramic to the metallic substrate was observed. The same phenomenon was also observed during deposition on FeSi6.5 samples. The successive deposition of YSZ on FeSi6.5 revealed a significant presence of YSZ ceramic on the FeSi6.5 samples. The formation of this deposit was found to be directly correlated with the number of remeltings performed on each layer. Indeed, the higher the number of remeltings, the more homogeneous and continuous the ceramic deposit observed across the entire sample Fig. 8 .b. Electron microscopy reveals the formation of an intermediate zone between FeSi6.5 and YSZ. Electron microscopy analysis shows that this zone is composed of Zr, Fe, and Si. This can be explained by the fact that during the fusion of YSZ, the melt pool depth exceeds the thickness of the YSZ layer and reaches the underlying FeSi6.5. As a result, the melt pool consists of a mixture of FeSi6.5 and YSZ. During solidification, the YSZ remains trapped within the FeSi6.5, forming this mixing zone. This zone corresponds to the diffusion of YSZ into FeSi6.5. The elemental composition of this zone varies depending on the number of remeltings of the YSZ deposited layer Fig. 8 .a, Fig. 8 .b. It is observed that, for a single fusion of YSZ on FeSi6.5,Fig. 8 , the Zr element is more concentrated in the contrast areas of the melt pool than in the core Fig. 9 . Moreover, the distribution of Zr is not homogeneous. However, as the number of layer remeltings increases, the distribution of Zr elements within the zone becomes more uniform. The thickness of the intermediate zone is approximately 50 µm across all samples, regardless of the number of remeltings of the Zr layer. Hardness measurements were carried out using a durometer along a line parallel to the fabrication plane, starting from the YSZ ceramic at point 0 and ending in the FeSi6.5 base material at 600 µm Fig. 9 . As shown in Fig. 10 , the highest hardness is observed in the YSZ ceramic, with a value of 848.9 HV. In the intermediate zone, a lower hardness of approximately 456.7 HV was recorded lower than that of YSZ but higher than that of FeSi6.5, whose hardness ranges between 337.5 and 363.9 HV. This increase in hardness in the intermediate zone can be attributed to the presence of ceramic material, which reinforces the FeSi6.5. 4. Conclusion In this study, we optimized the manufacturing parameters of FeSi6.5 and ZrO₂-Y₂O₃ materials within the framework of additive manufacturing by laser powder bed fusion (LPBF). The objective was to assess the feasibility of bi-material fabrication by defining the appropriate parameters for efficient and controlled production. A feasibility test was conducted to deposit ceramic (ZrO₂-Y₂O₃) on a FeSi6.5 substrate. A series of experiments was carried out to validate the ceramic deposition on FeSi6.5. The results obtained were satisfactory, paving the way for future work aimed at fabricating a layered structure of the FeSi6.5–ZrO₂-Y₂O₃–FeSi6.5 type. The results show good adhesion of the ZrO₂-Y₂O₃ ceramic after several laser passes over the deposited powder layer. The adhesion of the ceramic layer is directly dependent on the laser parameters used. Additionally, an intermediate zone was formed between the ceramic and the FeSi6.5. This zone mainly contains FeSi6.5, along with significant traces of Zr and Y, confirming the diffusion of elements. The thickness of the intermediate zone remains constant under the tested experimental conditions. Moreover, the hardness measured in this area is higher than that of FeSi6.5 alone, highlighting the potential of this transition zone to enhance the properties of the final material. These promising results provide a solid foundation for continuing the development of multilayer bi-material structures for advanced applications. Declarations Acknowledgements: The authors acknowledge the ANR – FRANCE (French National Research Agency) for its financial support of the FALSTAFF project N° ANR-22-CE08-0029-04 Declaration of Conflicts Interest: The authors declare that they have no competing financial interests. There are no competing interests related to this work. There are no known conflicts of interest associated with this publication. References « Magnetic and mechanical properties of additive manufactured Fe-3wt.%Si material », Journal of Magnetism and Magnetic Materials , vol. 580, p. 170907, août 2023, doi: 10.1016/j.jmmm.2023.170907. D. Goll et al. , « Additive manufacturing of soft magnetic materials and components », Additive Manufacturing , vol. 27, p. 428‑439, mai 2019, doi: 10.1016/j.addma.2019.02.021. G. Ouyang, X. Chen, Y. Liang, C. Macziewski, et J. 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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-6498025","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":452024104,"identity":"dd42c3f1-a0e6-49ce-b144-78b43ef9e83c","order_by":0,"name":"Mohamed Arezki AMITOUCHE","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/klEQVRIiWNgGAWjYFACHhDBDMSMDSBWAgN7A5jLT4yWxgawFp4DjM1AhmQDYS0QaxIYJBLwa9Ft7z346UaFNQP/tMPtDz622eXxS74xf1yYwyBhjkOP2ZlzydI5Z9IZJG4nNjbObEsulpydY9g8cxuDhMwBHFpu5BhI57YdZmAAamnmbTuQuOE2UAvvNoY6CRwOA2ox/p377zCDPEzL/ptnwFok8Ggxk85tOMxgALdFgoeAljNnzKxzjqXzGAK1zJxxLjlxxpm0wtkzt0ng1nK8x/h2To21nNzt9AcfPpTZJfa3H97wuXCbDU4tMMCDLkBIwygYBaNgFIwCfAAAWmdexoqyfoEAAAAASUVORK5CYII=","orcid":"","institution":"UTBM: Universite de Technologie de Belfort-Montbeliard","correspondingAuthor":true,"prefix":"","firstName":"Mohamed","middleName":"Arezki","lastName":"AMITOUCHE","suffix":""},{"id":452024105,"identity":"b526d2d5-67fe-4f56-99e8-016f4cd7a24c","order_by":1,"name":"Olivier Marconot","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Olivier","middleName":"","lastName":"Marconot","suffix":""},{"id":452024106,"identity":"ae0ca2fc-3bb4-423d-9674-58f97a4d4e2e","order_by":2,"name":"Yoann Donlos","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yoann","middleName":"","lastName":"Donlos","suffix":""},{"id":452024107,"identity":"9564f98b-3385-4894-8d36-298c0e8e77a8","order_by":3,"name":"Alejandro Ospina","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Alejandro","middleName":"","lastName":"Ospina","suffix":""},{"id":452024108,"identity":"b0975c46-8e3f-4241-b925-e8d604dc4b67","order_by":4,"name":"Nouredine Fenineche","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Nouredine","middleName":"","lastName":"Fenineche","suffix":""}],"badges":[],"createdAt":"2025-04-21 17:42:44","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6498025/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6498025/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":82239598,"identity":"ba5df141-152c-4ffc-8e04-1a74342cf5c1","added_by":"auto","created_at":"2025-05-08 07:46:38","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":202558,"visible":true,"origin":"","legend":"\u003cp\u003e.(a) Particle size distribution and (b) scanning electron microscopy (SEM) view morphology of Fe6.5%wtSi powder after sieving at 63μm mesh\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/16e7d13c818ca75175ee7728.png"},{"id":82239595,"identity":"8126a07c-8d1e-4c33-b4e8-1861c3b58a96","added_by":"auto","created_at":"2025-05-08 07:46:37","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":287979,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Particle size distribution and (b) scanning electron microscopy (SEM) view morphology of YSZ powder after sieving at 63μm mesh\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/26483d159f01d1d5ff9fd11f.png"},{"id":82239596,"identity":"35a7362a-df4a-459e-ade3-d88c50a500f4","added_by":"auto","created_at":"2025-05-08 07:46:37","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":289515,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Improvement device for an LPBF additive manufacturing machine, transitioning from a single-material configuration to a multi-material configuration. (b) Multi-material sample manufactured using the improvement device.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/2f4d7a73444ab97373271df2.png"},{"id":82240408,"identity":"8fe70491-1bde-4d1c-bc1a-2bf69e2c5ab7","added_by":"auto","created_at":"2025-05-08 07:54:38","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":678515,"visible":true,"origin":"","legend":"\u003cp\u003eIllustration of Additive Manufacturing Parameters: Pdist, Hdist, and Build Direction (XZ plane)\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/e510e0c6d4aba99b4e7357b9.png"},{"id":82239604,"identity":"acbf6719-6939-4d44-9916-f648431c0973","added_by":"auto","created_at":"2025-05-08 07:46:38","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":404069,"visible":true,"origin":"","legend":"\u003cp\u003eRepresentation of the experimental protocol for the sequential deposition of 1 to 5 layers of YSZ insulator, with repeated re-melting performed 1 to 3 times per layer.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/f5934513e64d936b66c80cbb.png"},{"id":82240404,"identity":"f5f61611-2e2b-4f9d-8bce-428bde2f2d4c","added_by":"auto","created_at":"2025-05-08 07:54:37","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":99811,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of density values as a function of VED over the course of the three test plans.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/97b971f63b0328c65855d6f5.png"},{"id":82239609,"identity":"f3222f58-e7ec-4f6f-a5e2-b65109c953a8","added_by":"auto","created_at":"2025-05-08 07:46:38","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":834221,"visible":true,"origin":"","legend":"\u003cp\u003eElectron Microscopy of a Sample: (a) FeSi6.5 and (b) ZrO₂-Y₂O₃\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/ec984241fb7a60a1fef189b8.png"},{"id":82239601,"identity":"89dc4fcd-0db8-40be-b69c-01933bcfc284","added_by":"auto","created_at":"2025-05-08 07:46:38","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":694737,"visible":true,"origin":"","legend":"\u003cp\u003eThese images depict samples consisting of five layers of ZrO₂-Y₂O₃ ceramic deposited on FeSi6.5.(a) Corresponds to the sample that underwent a single fusion for each ceramic layer. (b) Corresponds to the sample that underwent three fusions for each cera\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/15f46ad4e9cfeed97d95bb0a.png"},{"id":82240409,"identity":"74b4866f-7930-4e56-af5f-608117b212c6","added_by":"auto","created_at":"2025-05-08 07:54:38","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":365135,"visible":true,"origin":"","legend":"\u003cp\u003eThe image illustrates the percentage of zirconium measured at different points in the intermediate zone.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/4ec045c356ff22baed5d1037.png"},{"id":82239606,"identity":"323e2789-1a3a-40a7-88ce-8708d656bc54","added_by":"auto","created_at":"2025-05-08 07:46:38","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":542716,"visible":true,"origin":"","legend":"\u003cp\u003eHardness measurement on a sample along a line crossing the three zones: ZrO₂-Y₂O₃, intermediate zone, and FeSi6.5.\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/f29b9d980dbaccc73431bd00.png"},{"id":88930006,"identity":"b96a2a67-27c8-4aca-b9b7-a16f786bf0f2","added_by":"auto","created_at":"2025-08-12 20:54:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5265322,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6498025/v1/08aedac8-febd-4cf3-9100-6e1c22e9679c.pdf"}],"financialInterests":"","formattedTitle":"Feasibility study of a bi-materials magnetic laminate FeSi6.5/ceramic using powder bed fusion additive manufacturing","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eElectric machines (EM) are indispensable in modern industry, with diverse applications ranging from domestic uses to propulsion and electricity generation. They generate the world's electrical energy through electromechanical conversion. Given their growing importance, scientific research is constantly striving to improve their performance. For optimal energy conversion, it is essential to design innovative, high-performing, and cost-effective motors. The efficiency, durability, and cost of EMs depend heavily on the materials used. Soft magnetic materials play a key role for the stators. Their improvement is essential to increase machine performance, reducing energy losses and production costs. [1] [2]. Several innovative manufacturing techniques are used to produce these soft magnetic materials intended for electric machines. These technologies are specifically designed to address the challenges associated with their processing, which is often complex using conventional manufacturing methods. Among these advanced approaches, additive manufacturing stands out as a promising solution, offering greater flexibility and enhanced performance.\u003c/p\u003e \u003cp\u003eAdditive manufacturing of ferromagnetic materials presents a remarkable and evolving potential to improve both mechanical and magnetic properties. Among soft ferromagnetic alloys (FeSi, FeNi, FeCo, etc.), FeSi alloys, also known as ferromagnetic silicon steel, are the most widely used due to their optimal magnetic properties, including low coercivity (Hc = [50\u0026ndash;100 A/m]), high magnetic flux density (Bs = [1,6\u0026ndash;1,8 T]) and high relative permeability (\u0026micro;r = [10 000\u0026ndash;12 000]). [3] [4] Within the FeSi steel family, the 6.5%wt silicon alloy stands out for its high potential for applications in magnetic devices, this is due to its high electrical resistivity, which permits to decrease significantly Eddy Current losses for AC application, virtually zero magnetostriction and low magnetocrystalline anisotropy, making it a particularly suitable material for applications. [3] [4] [5], The inherent brittleness of high-silicon steels (\u0026gt;\u0026thinsp;3% wt Si) limits their manufacturing options. Additive manufacturing provides a versatile solution, allowing the production of these alloys with enhanced magnetic properties. [2] [4] [6]. Electric machines are designed with thin laminated sheets, separated by insulating layers, to effectively disrupt unwanted currents and reduce magnetic losses caused by eddy currents. However, while additive manufacturing enables the production of monolithic components with complex geometries, it does not allow for the integration of the lamination process used in electric motors. This limitation presents a major challenge in controlling eddy current losses, requiring solutions to optimize magnetic performance.[7] [8]\u003c/p\u003e \u003cp\u003eAdditive manufacturing creates new possibilities for producing intricate composites, particularly by alternately stacking insulating ceramic layers with magnetic metal layers. However, this configuration has been scarcely explored in the literature, and previous efforts have not yielded a fully satisfactory final stacking [2] [9] Our research marks a significant step forward in investigating the potential of layering ferromagnetic and ceramic materials, an approach that holds promise for improving the properties of electrical steels. This technology is essential for the advancement of electrical devices such as sensors, actuators, and heating elements. Nevertheless, although several commercial additive manufacturing systems exist, only a few are well-suited for multi-material production, making this a continuously evolving field.[10]\u003c/p\u003e \u003cp\u003eThe fabrication of functionally graded structures combining ceramics and steel necessitates the selection of a ceramic material with a coefficient of thermal expansion (CTE) closely matching that of steel. Zirconia (ZrO₂) is particularly well-suited for this purpose due to its thermal and mechanical compatibility with steel [11] [12]. The CTE of steel ranges between (11 \u0026times; 10⁻⁶ to 13 \u0026times; 10⁻⁶ K⁻\u0026sup1;)[13], while zirconia exhibits a CTE of 7.5 \u0026times; 10⁻⁶ K⁻\u0026sup1; at 20\u0026deg;C and 15.3 \u0026times; 10⁻⁶ K⁻\u0026sup1; at 1000\u0026deg;C [14], making it a viable candidate for integration with metallic phases. Experimental studies have demonstrated that zirconia-based materials can be successfully processed via selective laser melting (SLM) without the necessity for preheating .[11] [14] [9]. Pure zirconia is often referred to as \"ceramic steel\" due to its outstanding mechanical properties, including high fracture toughness and wear resistance. It exists in three primary crystallographic phases: monoclinic at low temperatures, tetragonal above 1170\u0026deg;C, and cubic beyond 2370\u0026deg;C. The transformation from the tetragonal to the monoclinic phase induces a volumetric expansion of approximately 3\u0026ndash;4%, which can lead to crack formation. To mitigate this issue, the incorporation of stabilizers such as yttrium oxide (Y₂O₃) enables the retention of the tetragonal phase at room temperature, thereby preventing phase transformation-induced damage. [11] [15] Despite its advantageous properties, zirconia poses significant challenges in additive manufacturing due to its high melting point and low absorption of laser energy [11] [16] H. Hayashi and al. [15] measured the CTE of yttria-stabilized zirconia (YSZ) with varying Y₂O₃ content (3, 6, 8, and 10 mol%), reporting average CTE values of 10.8 \u0026times; 10⁻⁶ K⁻\u0026sup1; and 10.1 \u0026times; 10⁻⁶ K⁻\u0026sup1; for 3 mol% and 8 mol% YSZ, respectively, over the temperature range of 298 K to 873 K. Additionally, Liu et al. [11] demonstrated that employing a secondary laser to preheat the powder bed prior to deposition significantly reduces cracking and defect formation in partially stabilized zirconia (YSZ). Preheating temperatures in the range of 1500\u0026deg;C to 2500\u0026deg;C have been found to effectively minimize residual thermal stresses and solidification-induced cracking. However, this approach remains technically challenging, resource-intensive, and is constrained to localized heating areas, limiting its industrial scalability.\u003c/p\u003e \u003cp\u003eIn this study, we have modified our laser powder bed fusion (LPBF) system, originally designed for single-material fabrication in a monolithic block, to enable the production of laminated materials. The primary objective is to alternate layers of ceramic and ferromagnetic FeSi6.5. Initially, we characterized the powders used for both materials, FeSi6.5 and ZrO₂-Y₂O₃, defining their essential properties to ensure optimal compatibility with the LPBF process. Subsequently, we detail the modifications implemented to facilitate multi-material fabrication. In the second phase, we optimize the processing parameters for each material individually to establish suitable manufacturing conditions. Following this, we develop and apply a deposition protocol for ZrO₂-Y₂O₃ ceramic onto ferromagnetic FeSi6.5, considering the thermal and physicochemical interactions between the two materials. Finally, in the results section, we present the fabrication outcomes for each material independently, followed by the results of the laminated composite structure. The study concludes with a comprehensive analysis of the findings, addressing the challenges encountered and the advancements achieved in the process.\u003c/p\u003e"},{"header":"2. Materials and procedures","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1. Powder characterization:\u003c/h2\u003e\n \u003cp\u003eThe characteristics of the powder play a crucial role in additive manufacturing, directly influencing process parameters and the final properties of the material. In this study, the raw material used is an atomized ferromagnetic silicon steel powder containing approximately 6.5 wt% Si. This powder was internally produced using UTBM\u0026rsquo;s atomizer. To enhance adhesion and flowability, it was dried at 80\u0026deg;C for 30 minutes. The particle size distribution ranges from 15 to 45 \u0026micro;m (D15 \u0026ndash; D45) Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003ea. A sieving process was performed to refine this distribution by removing particles larger than 63 \u0026micro;m. From a morphological perspective, the powder consists predominantly of spherical or quasi-spherical particles, which are characteristic of atomized powders. However, a smaller proportion of irregularly shaped particles is also present.\u003c/p\u003e\n \u003cp\u003eThis morphology results from the rapid solidification occurring during atomization. The particle surfaces are generally smooth, with occasional slight irregularities likely caused by splattering or partial coalescence of droplets during cooling Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eb. These characteristics directly influence the physical properties of the powder, including its flowability, packing density, and reactivity. As a result, this powder is particularly well-suited for applications in powder metallurgy, where a controlled particle size distribution is essential to ensure optimal performance in additive manufacturing.\u003c/p\u003e\n \u003cp\u003eThree ceramic compositions were evaluated in this study: ZrO₂-SiO₂ (33%), Al₂O₃-SiO₂ (24%), and ZrO₂-Y₂O₃ (7%). The objective was twofold: to assess the feasibility of fabricating these ceramics and to investigate their deposition on an FeSi6.5 substrate. Fabrication and deposition tests were conducted for each of the three compositions. Following these tests, ZrO₂-Y₂O₃ ceramic was selected for further studies. The ZrO₂-Y₂O₃ powder with 7% by weight of Y₂O₃ and particle size distribution between 15 and 45 \u0026micro;m (D22 - D45) Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e (a). To improve the homogeneity of the powder, sieving was performed to remove particles larger than 63 \u0026micro;m. SEM analysis of ZrO₂-Y₂O₃ powder reveals a morphology mainly composed of spherical and quasi-spherical particles Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eb. The particles exhibit relatively smooth surfaces and uniform dimensions, characteristics sought to ensure optimal packing density and good flowability, which are essential in additive manufacturing or sintering processes.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003eTable.1 presents a detailed analysis of the characteristics of FeSi and YSZ powders, comparing the compositions provided by producers with those obtained by Scanning Electron Microscopy (SEM). For FeSi, the composition is 6.4% silicon and 93.6% iron, while the SEM analysis reveals 6.2% Si and 95.35% Fe. For YSZ, the theoretical composition is 93% ZrO₂ and 7% Y₂O₃, whereas the SEM analysis shows 7.9% yttrium and 92.1% zirconium. The particle sizes for both powders range between 15 and 45 \u0026micro;m.\u003c/div\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003cem\u003eTable.1.Characteristics of FeSi6.5 and ZrO₂-Y₂O₃ Powders: Composition and Particle Size\u003c/em\u003e\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Taba\" border=\"1\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eType\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePowder Commercial Name\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePowder Manufacturer\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eManufacturer\u0026apos;s Composition\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSEM Composition\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSize (\u0026micro;m)\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\"\u003e\n \u003cp\u003eSoft Magnetic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFeSi6.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eUTBM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFe 6.5% Si\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6,4% Si \u0026minus;\u0026thinsp;93.6% Fe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15\u0026ndash;45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eceramic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYSZ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eH.C.Starck\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e93% ZrO\u003csub\u003e2\u003c/sub\u003e 7% Y₂O₃\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.9% Y₂O₃ \u0026minus;\u0026thinsp;92.1% ZrO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15\u0026ndash;45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2. Manufacturing process :\u003c/h2\u003e\n \u003cp\u003eThe experiments were carried out in a specific selective laser melting machine developed at the ICB-PMDM laboratory. A Realizer SLM250 machine. An Ytterbium fiber laser source with a maximum theoretical power output of 120 W and a wavelength of 1064 \u0026micro;m was used. The laser focus beam has a diameter of 34 \u0026micro;m. The building chamber dimension is 25 \u0026times; 25 \u0026times; 25 cm. The machine was filled with a shielding gas during all experiments to remove smoke and maintain a stable pressure. The chamber was purged of residual oxygen below 0.1% to avoid oxidation. The laser scanning mode was continuous. However, the laser displacement was driven by two mirrors fixed on a stepper motor to insure X and Y directions, with a galvanometric head. A continuous weld bead was formed point by point, with a distance Pdist between each point. The laser remained at each point for an exposure time of Texpo and then moves to the next point at the Pdist distance along the trajectory. Thus, Pdist and Texpo determine the effective scanning speed Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eThe system developed for integration into the LPBF machine consists of a powder distributor with two separate powder feeders, allowing the manufacturing machine to be fed with one or two powders Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003ea. This distributor operates with argon gas, which pushes the powder through a pipe into the build chamber. This system allows switching from one powder to another or simultaneous feeding with both. For spreading powder on the build bed, two powder inlet chambers are integrated into the coater. These two chambers are separate, and each chamber contains different materials.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3. Experimental process :\u003c/h2\u003e\n \u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e illustrates the adopted laser scanning strategy and the main variables influencing the fabrication of the samples. The deposition process consists of superimposing successive layers of material using a laser, with precise control over two key parameters: laser power (P) and scanning speed (V). Each laser pass generates a track of width h, defining the geometry of the deposited layer.\u003c/p\u003e\n \u003cp\u003eA specific scanning strategy has been implemented to ensure homogeneous construction and minimize residual stresses. This strategy is based on a 90\u0026deg; rotation of the laser beam orientation between successive layers. Thus: In the XY plane, which corresponds to the laser scanning plane and is perpendicular to the build direction, the material tracks are deposited in an alternating pattern between each layer. The XZ and YZ planes represent the side views parallel to the build direction, allowing for an analysis of the structure\u0026apos;s evolution as layers are progressively deposited.\u0026nbsp;\u003c/p\u003e\u003cp\u003eThis alternating scanning orientation between layers enhances thermal distribution, reduces the risk of distortion, and promotes uniform adhesion between layer critical factors in achieving a high-quality final part.\u003c/p\u003e\n \u003cp\u003eIn this work, we use the volumetric energy equation, which represents the main manufacturing parameters. The volume energy density (VED)(J/mm\u0026sup3;), corresponds to the energy density applied to a given volume and depends on several parameters: the laser power P (W); the laser scanning speed v (mm/s); the hatch distance h (mm), defining the distance between the lines traced by the laser beam; and t, the layer thickness (mm), corresponding to the thickness of the deposited powder bed Eq.\u0026nbsp;1.\u003c/p\u003e\n \u003cdiv id=\"Equa\" class=\"Equation\"\u003e\n \u003cdiv id=\"FileID_Equa\" class=\"mathdisplay\"\u003e$$\\:VED=\\frac{p}{vht},\\:\\:v=\\frac{p}{Eht}\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\:\\left(1\\right)$$\u003c/div\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003cdiv class=\"Section2\"\u003e\u003cem\u003ea) Monomaterial additive manufacturing\u003c/em\u003e:\u003cbr\u003e\n \u003cp\u003eIn order to optimize the manufacturing parameters of FeSi6.5 and achieve a higher density, an initial test plan was conducted. During this phase, 25 samples were fabricated with laser power between 73 W and 95 W and scanning speed between 0.34 m/s and 0.52 m/s. Surface density was assessed using image analysis. Among the different tested combinations, three power/speed pairs were selected for further investigation due to their higher density: 83 W, 88 W, and 95 W, with a speed of 0.41 m/s. In the second campaign, the speed was fixed at 0.41 m/s, and the power was maintained at the three previously selected values (83 W, 88 W, and 95 W). The distance between laser tracks (hd) was varied (20, 30, and 40 \u0026micro;m) to optimize track overlap and sample density. Results showed that a distance of 30 \u0026micro;m provided the highest densities. Finally, in the third plan, the distance between laser points (pdistance) was varied to increase energy density. The distance between tracks (hdistance) was fixed at 30 \u0026micro;m, the speed at 0.41 m/s, and the power was varied as before. The calculated exposure times, using Eq.\u0026nbsp;2, were 60, 80, and 100 \u0026micro;s. The optimal parameters determined from these three experimental campaigns are presented in Table.2\u003c/p\u003e\n \u003cp\u003eLiu et al [11], have shown that the fabrication of a YSZ ceramic on a ceramic substrate of the same material is possible. In our procedure, we chose to fabricate YSZ samples on a stainless-steel substrate because it is closer to the characteristics of FeSi6.5 and thus anticipate adhesion challenges. Various manufacturing parameters were studied to determine the optimal conditions for achieving the highest relative density. To this end, we maintained a constant layer thickness of 30 \u0026micro;m, the minimum achievable with our equipment, to approximate the thin insulating layers used in electric motors. The apparent relative density was determined by optical microscopy. In a first series of experiments, we varied the volumetric energy density from 133 to 253 J/mm\u0026sup3;, in steps of 30 J/mm\u0026sup3;. These values correspond to powers of 33 and 73 W, with an increment of 10 W. A total of 25 tests were conducted. Velocities were calculated using Eq.\u0026nbsp;(1), which relates volumetric energy density, power, and velocity. In a second series of experiments, we increased the volumetric energy density in increments of 100 J/mm\u0026sup3;, starting from 303 J/mm\u0026sup3; and reaching 503 J/mm\u0026sup3;. Simultaneously, we decreased the power in steps of 5 W, from 13 W to 33 W, to perform 25 tests. Among these results, we selected optimum parameters. To validate this result, we fabricated a sample on a ceramic substrate. All parameters are given in Table.2.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eTable.2. Operational Parameters of Test Campaigns for Additive Manufacturing of FeSi6.5 and ZrO₂-Y₂O₃ Materials by LPBF\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003ctable id=\"Tabb\" border=\"1\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMat\u0026eacute;riel\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eFeSi6.5\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eZrO₂-Y₂O₃ 7%\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\"\u003e\n \u003cp\u003eTest plan\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTest plan 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTest plan 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTest plan 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTest plan 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTest plan 2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLayer thickness, t (\u0026micro;m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHatch distance, h (\u0026micro;m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20, 30, 40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLaser power, P (W)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e73, 78, 83, 88, 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e83, 88, 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e83, 88, 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33, 43, 53, 63, 73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13, 18, 23, 27, 33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eScan speed, v (mm/s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e340, 370, 410, 460, 520\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e410\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e410\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e109\u0026ndash;457\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28\u0026ndash;121\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP distance P (\u0026micro;m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30,40,50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003evolume energy density j/mm\u0026sup3;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e78\u0026ndash;155\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e169\u0026ndash;386\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e224\u0026ndash;257\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e133,163,193,223,253\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e303,353,403,453,503\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSubstrate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eInox\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eInox\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlate temperature\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e240\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003e240\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAtmosphere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eArgon\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eArgon\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003cem\u003eb) Multi-material additive manufacturing\u003c/em\u003e :\u003c/p\u003e\n \u003cp\u003eThe objective is to create a FeSi6.5/ceramic/FeSi6.5 laminate. The adhesion of the ceramic layer is a crucial parameter for the laminate\u0026apos;s performance. In reference study [9], the number of powder layer remelting passes by laser was varied to improve the adhesion of this ceramic layer.\u003c/p\u003e\n \u003cp\u003eIn our work, fifteen FeSi6.5 samples (8\u0026times;8\u0026times;2 mm) were fabricated on a stainless steel substrate using optimal parameters. Subsequently, YSZ ceramic layers were deposited on these samples using optimized manufacturing parameters. To improve the adhesion of the layers, we studied the effect of the number of powder layer remelting passes (1, 2, or 3 remelting passes), while maintaining a constant manufacturing platform. At each remelting pass, the laser pass orientation was changed by 90 degrees. Additionally, we investigated the influence of the number of ceramic layers (1 to 5 layers) to determine the maximum thickness that allows obtaining a completely insulating ceramic layer with a less rough surface. Figure\u0026nbsp;5.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results and discussion ","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n\u003ch2\u003e3\u003cem\u003e.1. Monomaterial additive manufacturing results\u003c/em\u003e:\u003c/h2\u003e\n\u003cp\u003eFor the fabrication results of FeSi6.5, the internal density was measured using Archimedes' principle on samples taken directly from the fabrication platform. After cutting and polishing, surface densities were analyzed using an optical microscope. During the third test campaign, the sample with the highest density was selected under the following conditions: a constant velocity of 0.41 m/s, a fixed laser scan spacing of 30 \u0026micro;m, a laser spot spacing of 30 \u0026micro;m, and a power of 95 W. The apparent surface density, estimated by electron microscopy, was 98.93%, while Archimedes' method yielded an internal density of 97.09%. Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003ea.\u003c/p\u003e\n\u003cp\u003eThe results of the two test campaigns conducted for ZrO₂-Y₂O₃ ceramic show that, during the first series of experiments, the fabrication process was stopped as soon as a completely burned but unfused powder was observed. We found that all the samples subjected to a power of 33 W were the only ones to exhibit partial fusion. Analyzing the results for the five tested energy levels, ranging from 133 to 253 J/mm\u0026sup3;, we observed that low energy levels led to incomplete melting, while increasing the energy promoted fusion. This phenomenon can be explained by the refractory nature of our material to light. Indeed, its low thermal conductivity limits its ability to quickly absorb a large amount of energy. However, by using 30 \u0026micro;m layers, the energy can be better distributed, thereby facilitating fusion. Our objective is thus to provide enough energy to reach the high melting point of this material while avoiding local overheating caused by excessive power. Consequently, we designed a new series of experiments by reducing the power and increasing the fabrication energy. In our second test campaign, we observed that power levels of 13 and 18 W were insufficient to melt the powder, regardless of the tested energy levels. In contrast, for power levels of 23, 28, and 33 W, successful melting was achieved, enabling the fabrication of samples at all energy levels. These results allowed us to identify the optimal parameters for achieving the highest density. However, the samples fabricated under these optimal conditions did not exhibit good adhesion to the stainless-steel substrate.\u003c/p\u003e\n\u003cp\u003eThe parameters determined for ceramic processing in the remainder of the study are as follows: a relatively low laser power of 33 W, a scanning speed of 72 mm/s, a laser track spacing of 30 \u0026micro;m, and a layer thickness of 30 \u0026micro;m, corresponding to an energy density of 503 J/mm\u0026sup3;. Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e.b.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n\u003ch2\u003e3.2. \u003cem\u003eMulti-material additive manufacturing results\u003c/em\u003e:\u003c/h2\u003e\n\u003cp\u003eDuring the fabrication of YSZ ceramics on stainless steel substrates, poor adhesion of the ceramic to the metallic substrate was observed. The same phenomenon was also observed during deposition on FeSi6.5 samples.\u003c/p\u003e\n\u003cp\u003eThe successive deposition of YSZ on FeSi6.5 revealed a significant presence of YSZ ceramic on the FeSi6.5 samples. The formation of this deposit was found to be directly correlated with the number of remeltings performed on each layer. Indeed, the higher the number of remeltings, the more homogeneous and continuous the ceramic deposit observed across the entire sample Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e.b.\u003c/p\u003e\n\u003cp\u003eElectron microscopy reveals the formation of an intermediate zone between FeSi6.5 and YSZ. Electron microscopy analysis shows that this zone is composed of Zr, Fe, and Si. This can be explained by the fact that during the fusion of YSZ, the melt pool depth exceeds the thickness of the YSZ layer and reaches the underlying FeSi6.5. As a result, the melt pool consists of a mixture of FeSi6.5 and YSZ. During solidification, the YSZ remains trapped within the FeSi6.5, forming this mixing zone. This zone corresponds to the diffusion of YSZ into FeSi6.5. The elemental composition of this zone varies depending on the number of remeltings of the YSZ deposited layer Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e.a, Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e.b.\u003c/p\u003e\n\u003cp\u003eIt is observed that, for a single fusion of YSZ on FeSi6.5,Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e, the Zr element is more concentrated in the contrast areas of the melt pool than in the core Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e. Moreover, the distribution of Zr is not homogeneous. However, as the number of layer remeltings increases, the distribution of Zr elements within the zone becomes more uniform.\u003c/p\u003e\n\u003cp\u003eThe thickness of the intermediate zone is approximately 50 \u0026micro;m across all samples, regardless of the number of remeltings of the Zr layer.\u003c/p\u003e\n\u003cp\u003eHardness measurements were carried out using a durometer along a line parallel to the fabrication plane, starting from the YSZ ceramic at point 0 and ending in the FeSi6.5 base material at 600 \u0026micro;m Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e.\u003c/p\u003e\n\u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e, the highest hardness is observed in the YSZ ceramic, with a value of 848.9 HV.\u003c/p\u003e\n\u003cp\u003eIn the intermediate zone, a lower hardness of approximately 456.7 HV was recorded lower than that of YSZ but higher than that of FeSi6.5, whose hardness ranges between 337.5 and 363.9 HV.\u003c/p\u003e\n\u003cp\u003eThis increase in hardness in the intermediate zone can be attributed to the presence of ceramic material, which reinforces the FeSi6.5.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eIn this study, we optimized the manufacturing parameters of FeSi6.5 and ZrO₂-Y₂O₃ materials within the framework of additive manufacturing by laser powder bed fusion (LPBF). The objective was to assess the feasibility of bi-material fabrication by defining the appropriate parameters for efficient and controlled production.\u003c/p\u003e \u003cp\u003eA feasibility test was conducted to deposit ceramic (ZrO₂-Y₂O₃) on a FeSi6.5 substrate. A series of experiments was carried out to validate the ceramic deposition on FeSi6.5. The results obtained were satisfactory, paving the way for future work aimed at fabricating a layered structure of the FeSi6.5\u0026ndash;ZrO₂-Y₂O₃\u0026ndash;FeSi6.5 type.\u003c/p\u003e \u003cp\u003eThe results show good adhesion of the ZrO₂-Y₂O₃ ceramic after several laser passes over the deposited powder layer. The adhesion of the ceramic layer is directly dependent on the laser parameters used. Additionally, an intermediate zone was formed between the ceramic and the FeSi6.5. This zone mainly contains FeSi6.5, along with significant traces of Zr and Y, confirming the diffusion of elements.\u003c/p\u003e \u003cp\u003eThe thickness of the intermediate zone remains constant under the tested experimental conditions. Moreover, the hardness measured in this area is higher than that of FeSi6.5 alone, highlighting the potential of this transition zone to enhance the properties of the final material.\u003c/p\u003e \u003cp\u003eThese promising results provide a solid foundation for continuing the development of multilayer bi-material structures for advanced applications.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors acknowledge the ANR – FRANCE (French National Research Agency) for its financial support of the FALSTAFF project N° ANR-22-CE08-0029-04\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration of Conflicts Interest: \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing financial interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThere are no competing interests related to this work.\u003c/p\u003e\n\u003cp\u003eThere are no known conflicts of interest associated with this publication.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003e\u0026laquo;\u0026nbsp;Magnetic and mechanical properties of additive manufactured Fe-3wt.%Si material\u0026nbsp;\u0026raquo;, \u003cem\u003eJournal of Magnetism and Magnetic Materials\u003c/em\u003e, vol. 580, p. 170907, ao\u0026ucirc;t 2023, doi: 10.1016/j.jmmm.2023.170907.\u003c/li\u003e\n\u003cli\u003eD. 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Raffaelli, \u0026laquo;\u0026nbsp;An overview of zirconia ceramics: Basic properties and clinical applications\u0026nbsp;\u0026raquo;, \u003cem\u003eJournal of Dentistry\u003c/em\u003e, vol. 35, n\u003csup\u003eo\u003c/sup\u003e 11, p. 819‑826, nov. 2007, doi: 10.1016/j.jdent.2007.07.008.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6498025/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6498025/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"The ferromagnetic material FeSi6.5 exhibits lower magnetic losses compared to the more widely used FeSi3, commonly employed in the production of laminated sheets for stators and rotors. This makes FeSi6.5 a promising candidate for electric motor manufacturing. However, its high silicon content complicates significantly production through conventional lamination processes. Additive manufacturing emerges as a viable alternative for this application. In electric motors, laminated sheets are separated by insulating layers to reduce eddy current losses. While additive manufacturing allows the fabrication of complex shapes, it is currently limited to single-material structures and cannot replicate the laminated architecture of electric motors. Research on multi-material additive manufacturing remains in its early stages of development.\nThe challenge is to manufacture laminated electric motors using additive manufacturing, with thin ceramic insulating layers and ferromagnetic FeSi6.5 material layers. To achieve this, we have developed an innovative system to modify our LPBF manufacturing machine to work with two materials. This paper presents our work on the modification of our LPBF machine for the bi-material process, as well the ceramic/metal interface optimization.","manuscriptTitle":"Feasibility study of a bi-materials magnetic laminate FeSi6.5/ceramic using powder bed fusion additive manufacturing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-08 07:46:33","doi":"10.21203/rs.3.rs-6498025/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b508163b-a11b-46ab-9b5b-d53b97878f5c","owner":[],"postedDate":"May 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-12T20:46:08+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-08 07:46:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6498025","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6498025","identity":"rs-6498025","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}