Additive manufacturing (AM) offers a unique opportunity to revisit historically brittle alpha 2-Ti3Al alloys by exploiting rapid solidification to retain metastable, crack-tolerant phases during fabrication while enabling transformation to alpha 2for service. Here, we develop a beta-solidifying alpha 2-based Ti-Al alloy tailored for laser powder bed fusion (L-PBF) using a combined Mo-equivalent (Moeq) and Thermo-Calc equilibrium design strategy. A target composition of Ti-28Al-2.4Nb-0.6Mo-1.8 V (at%) (Moeq approximate to 4.2 wt%) was realized via in-situ alloying by blending two commercial powders (TNM-B1 and Ti-6Al-4V). Crack-free, near-fully dense components (-99.9% relative density) were produced using low scanning speeds, demonstrating that metastable beta retention can be achieved at substantially lower Moeq than in conventional alloy design for beta solidifying titanium alloys. Room-temperature synchrotron X-ray diffraction (SXRD) shows the as-built microstructure is dominated by retained beta with weak B2 ordering (B2{100}/beta{110} approximate to 0.05). In-situ high-temperature SXRD (300-600 degrees C) reveals a staged transformation pathway: beta/B2 (partially ordered) -> beta (disordered) -> alpha (disordered) -> alpha/alpha 2(partially ordered), with alpha 2superlattice reflections emerging above-500 degrees C. Post-build heat treatment (PBHT) at 600 degrees C/8 h eliminates beta/B2 and yields an alpha/alpha 2-dominated microstructure. Hot tensile testing at 750 degrees C shows an ultimate tensile strength of 356.9 MPa with 4.7% total strain and an extended post-ultimate elongation to 17.3% (sigma fra approximate to 195 MPa), exceeding reported ductility for laser-AM TiAl. Finally, crack-free macro-functionally graded structures between Ti-6Al-4V and the developed alloy were demonstrated, highlighting a pathway for bimetallic high-temperature components and coatings.

Porous Ti-6Al-4V (Ti64) fabricated by laser powder bed fusion (L-PBF) exhibits permeability and mechanical behavior that depend strongly on porosity percentage and pore architecture. In this work, Ti64 designed materials containing dense and process-induced porous regions were manufactured within a single build by systematically varying hatch spacing and interlayer scan rotation using 67 degrees and 90 degrees scan strategies. X-ray computed tomography (XCT) quantified pore size distribution, connected porosity, and directional tortuosity, and these features were correlated with Darcy permeability and mechanical response under tension, compression, and creep. Increasing hatch spacing enlarged inter-track gaps, raising total porosity from similar to 8% to similar to 20% and shifting average pore diameter from similar to 50 to 60 mu m to similar to 100-110 mu m. However, permeability was governed not by porosity alone but by pore network topology. The 90 degrees strategy produced aligned, low-tortuosity channels (tau = 1.6-2.1) with up to similar to 50% pore connectivity, resulting in 2.4-7.9 times higher permeability than the more tortuous 67 degrees networks (tau = 2.8-3.5). Mechanical response exhibited topology-dependent trade-offs. Tensile strength decreased monotonically with porosity (700 to 350 MPa), whereas compressive and creep behavior were strongly influenced by pore connectivity and alignment. The 67 degrees strategy preserved higher ultimate compressive strength (up to 1239 MPa) and reduced creep strain despite higher porosity by disrupting continuous weak channels. These results establish a quantitative topology-transport-mechanics framework and demonstrate scan strategy as a pore-topology design variable for tailoring permeability-strength trade-offs in L-PBF porous structures.

Semiconductors underpin modern electronics, optoelectronics, sensing, and energy technologies, yet their manufacturing remains dominated by centralized, tool-intensive, and largely planar process flows. Additive manufacturing (AM) offers a complementary pathway that can reduce material waste, accelerate prototyping, and unlock three-dimensional (3D) semiconductor architectures that are difficult to realize using conventional fabrication. However, AM of semiconductors is still in its infancy and has been demonstrated for only a limited set of materials and processes. This perspective synthesizes the current landscape of semiconductor AM by compiling reported 3D-printable semiconductor systems and mapping them to the corresponding AM techniques, including laser powder bed fusion, selective laser sintering, gas-phase reactive AM, inkjet printing, electrohydrodynamic redox printing, two-photon lithography, aerosol jet printing, extrusion-based AM, and laser-directed energy deposition. The key process-specific barriers are critically discussed—spanning feedstock limitations, densification and cracking, stoichiometry control and volatilization, texture and compositional heterogeneity, post-processing burdens, contamination, and scalability. On this basis, a length-scale–guided roadmap is proposed: laser powder bed fusion is positioned as the most promising route for cm–mm thermoelectric architectures, with advances in substrate/feedstock design, atmosphere control, and microstructure/defect engineering; ink-based and reactive approaches are highlighted for sub-mm to micro-scale functional devices through improved ink chemistry, 3D buildup, and multi-material integration; and electrohydrodynamic redox printing/two-photon lithography are identified as leading candidates for sub-micron to nanoscale fabrication, where material diversification, low-temperature conversion, residue mitigation, and hybrid integration with conventional microfabrication are essential. Collectively, this perspective clarifies terminology, consolidates the emerging evidence base, and outlines research priorities required to transition semiconductor AM from proof-of-concept demonstrations toward robust, application-relevant device manufacturing.

Cobalt and cobalt carbides play an essential role in enhancing the magnetic properties, hardness, and durability of advanced magnetic materials. These desirable characteristics originate from their high magnetic moment, favorable Curie temperature, and structural stability. In this study, CoxC/Co nanocomposite powders containing different amounts of samarium were synthesized using the polyol method. The influence of samarium content on the structural and magnetic properties of the nanopowders was systematically investigated. The synthesized powders were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and first-order reversal curve (FORC) measurements. The XRD analysis indicated that samarium addition facilitated the formation of the metallic cobalt phase. The crystallite size was calculated using the Scherrer method, with the phase percentages determined by the Rietveld method. Increasing the samarium content from 1 to 3 wt.% resulted in an increase in the crystallite size from 19 to 27 nm and an increase in the metallic cobalt fraction from 11 to 26 wt.%. These results suggest that samarium may play a kinetic modifier role in promoting metallic cobalt formation during the polyol process. The microscopic observations were in good agreement with the XRD findings. The magnetic measurements further confirmed that the saturation magnetization increased markedly from 94 to 144 emu/g as the samarium content increased from 1 to 3 wt.%.

Precise control over the coexistence of soft and hard magnetic phases in magnetic nanowire arrays (NWAs) is crucial for optimizing their performance in spintronic and high-density magnetic storage applications. This study focuses on manipulating soft and hard magnetic phases in cobalt (Co) NWAs via controlled copper pre-electrodeposition and NW diameter variation. Co NWAs with diameters of 30nm and 60nm were prepared by pulsed electrodeposition into anodic aluminum oxide templates. First-order reversal curve diagrams and switching field distribution provided deep insights into the interplay of inter-wire magnetostatic interactions and intra-wire exchange coupling. It has also been shown that Cu pre-electrodeposition on NWAs with a diameter of 60nm significantly affects magnetic behavior compared to that of 30nm. The microstructure investigation results showed that copper pre-deposition influenced the crystalline growth orientation, promoting the formation of the magnetically hard (002) hexagonal close-packed (hcp)-Co phase at the expense of the soft (100) hcp-Co phase. Magnetic measurements demonstrated that an optimum of Cu pre-electrodeposition (e.g., 0.10C for 30nm NWs) enhances the coercivity and squareness ratio, achieving values of 1659Oe and 0.81, respectively. This study examined through micromagnetic simulations how diameter and magnetocrystalline orientation affect magnetization reversal, the shape of the hysteresis loop, and inter-wire interactions. It was found that a 60nm diameter promotes vortex-mediated reversal, and stronger magnetostatic interactions reduce coercivity. The work provides a suitable strategy for designing exchange-coupled composite NWAs with tailored magnetic properties for advanced applications in spintronics and high-density data storage.

Abstract Carbon fiber–reinforced silicon nitride (Cf/Si3N4) composites were fabricated by spark plasma sintering (SPS) using α-, β-, and γ-Si3N4 powders to clarify the influence of the initial Si3N4 phase on microstructural evolution and functional properties. The results show that the starting phase significantly affects densification behavior, phase transformation, and mechanical and tribological performance. The composite derived from α-Si3N4 achieved the highest relative density (96.53%) and exhibited an optimal balance of fracture toughness (10.87 MPa m0.5), thermal conductivity (66 W/m K), and stable friction behavior (COF ≈ 0.46). This performance is attributed to the in-situ formation of a self-reinforced β-Si3N4 microstructure during the α → β phase transformation, which promotes crack deflection, crack bridging, and effective load transfer in synergy with carbon fibers. In contrast, β- and γ-Si3N4–based composites showed lower densification or excessive hardness associated with increased porosity and secondary phase formation. These findings demonstrate that controlling the initial Si3N4 phase provides an effective microstructural design strategy for developing high-performance Cf/Si3N4 composites for thermostructural applications such as aerospace brake discs.

In laser powder bed fusion (LPBF), support structures are conventionally used to anchor parts and mitigate distortion during fabrication. Here, we show that support structures can be engineered to control heat dissipation and harness intrinsic process heat for in-situ heat treatment (IHT) of precipitation-hardenable Al alloys. Using Scalmalloy (R) as a model system, preliminary process-parameter screening of unsupported samples showed that intrinsic process heat could produce only modest in-situ hardening at very high volumetric energy density, and this was accompanied by severe porosity. To overcome this density-hardness trade-off, low-area-fraction supports (LAFS) were introduced to promote IHT through reduced heat dissipation rather than excessive localized heat input. The use of LAFS was found to significantly prolong high-temperature exposure during layer-by-layer fabrication, thereby promoting substantial in-situ strengthening in the as-built state. Atom probe tomography revealed a high number density of Sc-rich clusters, which are identified as the dominant strengthening feature in the LAFS samples. By combining LAFS with interlayer time control, the hardness profile could be tailored to produce either gradient or near-uniform distributions. Tensile testing showed that the combined use of LAFS and a graded interlayer time strategy produced a yield strength of 453 MPa and an ultimate tensile strength of 479 MPa in the as-built state, achieving almost identical tensile performance to conventionally peak-aged Scalmalloy (R). Multiscale thermal simulations established a quantitative link between local thermal histories and mechanical response through an equivalent aging framework. These results demonstrate the potential of using LAFS as a process-integrated tool for activating IHT in precipitation-hardenable Al alloys during LPBF without compromising densification, providing a practical route to reduce reliance on post-build heat treatment.

Friction Stir Processing (FSP) is an effective technique to refine microstructures and improve the weldability of crack-prone aluminum alloys such as AA6061. However, this study reveals that during fusion welding of FSP-treated AA6061, abnormal grain growth (AGG) can occur due to prolonged thermal exposure, especially in the heat-affected and partially melted zones. AGG compromises microstructural uniformity and promotes liquation and solidification cracking, diminishing the crack resistance benefits of FSP. Experimental results demonstrate that while FSP suppresses cracking in short welds, extended weld lengths increase thermal accumulation, intensifying AGG and crack susceptibility. These findings emphasize the critical need for precise control of welding parameters and thermal management to maintain microstructural stability and joint integrity. Effective mitigation of AGG through alloy design, process optimization, and heat input control is essential to fully leverage the potential of FSP in advanced manufacturing and fusion welding applications.

The successful fabrication and implementation of graphene-reinforced aluminum (Al) matrix composites (AMCs) have been obstructed by the undesirable graphene-Al reactions during their casting or inability of complex part manufacturing through powder metallurgy techniques. The emergence of the laser powder bed fusion (L-PBF) process with extremely short melt duration and almost no limitations in terms of the manufacturing of intricate features has renewed the interests for fabrication of graphene-reinforced AMCs. In this study, the influence of graphene incorporation into AlSi12 on L-PBF processability and defect formation is studied. The specific heat capacity, coefficient of thermal expansion, thermal diffusivity and thermal conductivity of composites were compared to those of the monolithic AlSi12 alloy. Microstructure-thermal properties relationship was studied through transmission electron microscopy (TEM), high-resolution TEM (HRTEM), electron backscatter diffraction (EBSD), electron dispersive spectroscopy (EDS) and Raman spectroscopy. This study provides valuable insights into (i) the chance of survival of graphene, (ii) possibility of graphene changing into other forms of carbon, and (iii) graphene-Al reactions during the L-PBF process. It was found that most of the graphene/graphite particles transformed into Al4C3. 4 C 3 . Among the survived carbon material, it appears they are more disordered than the initial graphene/graphite, though highly ordered ones with almost no defects were also detected. Thermal expansion measurements showed that the coefficient of thermal expansion decreased from 27.5x10-6/& ring;C x10-6/& ring;C for AlSi12 to 25.3x10-6/& ring;C x10-6/& ring;C for AlSi12-0.25 Gr and 25.5x10-6/& ring;C x10-6/& ring;C for AlSi12-0.5 Gr. Regarding thermal conductivity, in the case of AlSi12-0.5 Gr, it either matched or was lower than that of pure AlSi12 within the tested temperature range. In contrast, AlSi12-0.25 Gr exhibited higher thermal conductivity than AlSi12 in the temperature range of 150-350 & ring;C.

First-order reversal curve (FORC) analysis is known to provide a precise evaluation of the magnetic properties of different magnetic alloys, thereby encouraging their development for high-quality and practical applications. However, the magnetic behavior of FeCrCo alloy is yet to be investigated and realized comprehensively. Here, the effect of magnetic field annealing on microstructural, magnetic, and mechanical characteristics of Fe-25Cr-15Co-3Mo-0.3Ti alloy is studied using field-emission scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, and Vickers hardness measurement. The magnetic annealing processes are performed at various temperatures ranging from 600 to 640 °C. The single-phase structure of the resulting alloy is formed following solid solution annealing and quenching in water. An optimum temperature of 625 °C is found to be suitable for the growth of the α1 phase using the magnetic annealing process. Although hysteresis loops indicate a maximum coercivity value of 541 Oe, FORC analysis reveals a higher mean coercivity of individual α1 nanoparticles. Moreover, FORC diagrams evidence the presence of magnetostatic interactions, which increase with increasing the magnetic annealing temperature to 630 °C and then decrease for higher annealing temperatures. Moreover, an aging time of 135 min enhances the remanence and reduces the coercive field distribution of Fe-25Cr-15Co-3Mo-0.3Ti alloy. Depending on the magnetic annealing conditions, the mechanical hardness of the alloys varies from 460 to 500 HV due to lattice misfit. The results reveal that the FORC analysis provides new insights into a spinodal decomposition process, thereby allowing for the future development of FeCrCo magnetic alloys.

This study investigates wire arc additive manufacturing (WAAM) also known as wire-arc directed energy deposition (WA-DED) of type 430 ferritic stainless steel, with a focus on the microstructural characteristics and mechanical behavior of the printed component. The WAAM system utilized a gas metal arc welding (GMAW)based approach to produce a single-track multi-layer component. Microstructural analysis was conducted using a dual approach, combining Thermo-Calc/JMatPro calculations for theoretical insights, and light optical microscopy, field-emission scanning electron microscopy (FESEM), and electron backscatter diffraction (EBSD) for experimental investigations. The microstructure of WAAM-printed 430 steel is characterized by the formation of large columnar alpha-ferrite grains decorated with fine intragranular Cr-rich carbides, grain boundary martensite, and the formation of a precipitation-free zone (PFZ) near the martensite layer. These microstructural features of WAAM-printed 430 steel resulted in deficiencies in ultimate tensile strength and ductility, compared to wrought AISI 430 steel. The study highlights the need for implementing an effective strategy for grain refining and designing a tailored post-build heat treatment to enhance the strength and ductility of the printed 430 ferritic stainless steel.

This research explores the thermal and mechanical properties of a CuNi2SiCr alloy made by laser powder bed fusion (LPBF) for potential use in the neck insert of extrusion blow molds. Process parameter optimization, aging heat treatment design, thermal and mechanical property characterizations, microstructural analysis, and an exploration of the factors affecting thermal conductivity are presented. Results showed that the aging thermal cycle significantly enhanced the thermal conductivity of the as-build sample from similar to 70 W/mK) to similar to 180 W/mK. Numerical analysis of the involvement of various scattering phenomena in the overall mean free path of conducting electrons revealed that such a significant increase in thermal conductivity originated from the emergence of nanoscale Ni, Cr, and Si containing precipitates from the supersaturated matrix which depleted the matrix of extrinsic scattering sites accounting for similar to 80 % of electron scattering in the as-built specimen. The sample subjected to heat treatment showed a 95 % increase in nanohardness and significantly higher yield strength (575 MPa) and ultimate tensile strength (687 MPa) compared to the as-built specimen (236 MPa and 291 MPa, respectively). The improvements obtained in this study in both thermal and mechanical properties showcase the potential of LPBF and subsequent heat treatment in enhancing Cu alloy materials for various industrial applications.

This study employs a novel processing approach using laser powder bed fusion (L-PBF). It leverages rapid cooling to develop a metastable microstructure that can retain or revert to suit both room and high-temperature applications. This approach is paired with a cost-effective blending strategy to fabricate novel alloys with microstructures that integrate ductile and hard phases. The study demonstrates the effectiveness of this approach in significantly enhancing the creep performance of Ti-6Al-4V (wt%) through in situ alloying with Ti-48Al-2Cr-2Nb (at%) at weight fractions of 20 % and 40 % via L-PBF. A tailored microstructure was achieved, leading to crack free samples. X-ray diffraction (XRD) phase analysis identified a metastable microstructure comprising the ductile beta phase alongside hard alpha/alpha '/alpha 2 phases. A significant presence of beta phases was observed in the 40 % TiAl alloy, comprising 80 % of the scanned area according to electron backscatter diffraction (EBSD) analysis, demonstrating the influence of rapid cooling in retaining high-temperature phases. Results from transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and selected area electron diffraction (SAED) indicated a high dislocation density within the alpha phase, which contributed to crack nucleation during mechanical testing. The heat-treated alloys, in which the beta phase revert to alpha 2, exhibited creep lifetime that surpassed Ti64 by 380 % for the 20 % TiAl alloy and over 600 % for the 40 % TiAl alloy. The combination of beta and alpha phases at room temperature contributed to a yield strength of 966 MPa for 20 % TiAl and 741 MPa for 40 % TiAl, along with elongation percentages of 6.8 % for 20 % TiAl and 3.2 % for 40 % TiAl, both of which surpassed those of TiAl. These results pave the way for processing other materials beyond these specific alloys, enabling a wide range of applications.

Failure of valves in heavy-duty diesel engines is a significant challenge for engine reliability. This study aims to investigate the metallurgical factors that led to the failure of several exhaust valves made from a nitrogen-containing Fe-Mn-Cr-Mo-Nb-V alloy. The failures predominantly occurred in the hot section of the valve stem and were attributed to environmentally assisted fatigue. The primary cause of failure was identified as the low thermal stability of the valve microstructure, characterized by a high-volume fraction of discontinuous cellular precipitation of M23C6/austenite in the hot section of the valve stem. This microstructural instability played a crucial role in initiating and propagating corrosion/oxidation-assisted fatigue cracks due to the precipitation of low toughness Cr-rich carbides and formation of associated Cr-depleted zone the subsequent creation of Cr-depleted areas. To mitigate similar failures in heavy-duty diesel engines operating under increased peak cylinder pressures and temperatures, it is imperative to utilize materials with higher thermal stability and improved corrosion/oxidation resistance.

The present paper set out to investigate the synthesis and electromagnetic characterization of Ti3AlC2 MAX phase and Ti3C2Tx MXene in Ti-Al-C ternary system. In this regard, Ti3AlC2 MAX phase was synthesized using mechanical milling process of TiC, Al, and Ti powder mixtures based on 2TiC-Al-Ti+xAl (x=0, 0.25, 0.5, 0.75 and 1). The HF acidic etching was also employed to synthesize the Ti3C2Tx MXene. Structural and electromagnetic characterizations of the prepared samples were conducted using X-ray diffraction (XRD), scanning electron microscopy (SEM) and vector network analyzer. The obtained results point to the impossibility of the formation of Ti3AlC2 single-phase structure in stoichiometric system. In other word, development of the Ti3AlC2 single-phase structure is only possible in non-stoichiometric 2TiC-2Al-Ti system. The minimum reflection losses of the prepared Ti3AlC2 MAX phase was estimated to be around -30.73 dB at the matching frequency of 15.25 GHz. The results further revealed that the etching time affects electromagnetic behavior of the MXene. That is, an increase in the etching time brings about a change in the reflection loss (RL) from -24.17 to -5.69 dB within the frequency range of 1-18 GHz.

With the development of 3D metal printers for rapid prototyping and industrial component production, heightened attention was directed towards post-processing operations for achieving precise surface quality and geometrical tolerances for these components. This paper investigated the orthogonal cutting of multi-material 3D printed workpieces using a coated cutting tool through finite element simulation. The workpieces featured different horizontal and vertical arrangements of layers composed of aluminum 7075-T6 alloy (Al), stainless steel 316 low alloy (SS), and Ti6Al4V alloy (Ti). The study explored the impacts of multi-material composition, coating thickness, and the rake angle of the cutting tool on machining forces, stress distribution, temperature distribution, and chip formation geometry. The results revealed a bimodal chip morphology in the machining process of horizontally arranged SS layers combined with other alloys. The SS layer resulted in a relatively uniform chip formation, while layers with two other materials exhibited a serrated chip formation. In contrast, a discontinuous chip formed when combining Al and Ti materials, as well as in the horizontally arranged layers made of Al, SS, and Ti alloys. The cutting force increased by 2.26 times when cutting workpieces with the horizontal arrangement of SS and Al layers compared to those with a single Al material. For the horizontal and vertical arrangement of layers made of Al and SS, von Mises stress values over the edge of the coated cutting tool significantly increased where the tool contacted the SS layer. Additionally, the horizontal arrangement of layers made of Al and SS materials caused the coated cutting tool to exhibit an extensive temperature distribution, with the maximum recorded temperature reaching 1448 °K. Increasing coating thickness led to a decrease in maximum principal stress at the surface of the tool and a rise in temperature at the cutting edge of the insert.

The AA7075 high-strength aluminum alloy exhibits a pronounced tendency for hot cracking during fusion welding, which hampers its widespread utilization in lightweight design concepts. This study aims to investigate the effectiveness of friction stir processing (FSP) as a pre-weld treatment to eliminate the occurrence of hot cracking during fusion welding of the AA7075 aluminum alloy. Our findings demonstrate that the FSP pre-weld treatment successfully suppresses liquation cracking in the AA7075 alloy, even when utilizing ER1050 filler metal for welding, which poses a considerable risk of liquation cracking. The FSP treatment induces a transformative effect on the microstructure of the hot-rolled material, leading to the conversion of the typical large elongated pancake-shaped grains into refined recrystallized grains. Electron backscatter diffraction (EBSD) analysis confirms the introduction of finer grains, characterized by an increased grain boundary area, and higher volume fraction of low angle grain boundaries within the partially melted zone (PMZ) of the friction stir processed base metal. This leads to a reduction in the thickness of the liquid film and consequently diminishes the susceptibility to liquation cracking. These findings prove that arc welding with FSP pre-weld treatment is an enabling welding strategy for producing high-performance AA7075 joints.

In the present research, the effect of the Ge: C ratio was evaluated and explained on the bonding structure, the hardness, and residual stress of germanium-carbon (Ge1-x-C-x) coatings fabricated by plasma-enhanced chemical vapor deposition (PECVD) method. For characterizing the coatings, a field emission scanning electron microscope (FE-SEM) equipped with an energy dispersive spectrometer (EDS), transmission electron microscope (TEM), Raman spectrometer, Rutherford backscattering spectrometer (RBS), elastic recoil detection (ERD) analysis, X-ray photoelectron spectrometer (XPS), nanoindentation test, and cohesion test were used. by increasing the flow rate ratio of CH4:GeH4 and as a result of decreasing the ratio of Ge: C, the fraction of sp(2) C-C and sp(3) Ge-C bonds were increased and the fraction of Ge-Ge bonds was decreased. The hardness of the Ge1-x-C-x coatings was heavily reliant on changes in the Ge: C ratio and, consequently, the fraction of the bonds incorporated within the coating structure. To achieve a hard coating, the selection of a moderate carbon content is very important such that it would lead to the formation of maximum sp(3) Ge-C bonds alongside slight amounts of sp(2) C-C and hydrogen bonds. For very low carbon concentrations, the existence of dominant Ge-Ge bonds would create the coating structure as germanium-like; the excessive rise of the carbon concentration promotes the undesirable graphite-like structures. In the optimum conditions, the hardness of the coating was obtained at 10.1 GPa. The coatings presented a very low residual stress (similar to 98-240 MPa) despite having suitable hardness.

Laser powder bed fusion (LPBF) is a pivotal method in metal additive manufacturing, enabling the intricate fabrication of complex components. However, the rapid thermal transitions inherent in LPBF can induce residual stresses, potentially leading to defects like distortions, cracks, and delamination. This research aims to investigate the distribution of temperature and stress during the LPBF manufacturing of Inconel 625, as well as the generation of residual stresses. For this purpose, a three-dimensional finite element (FE) model of the LPBF process was developed to explore the influence of various factors, including the number of layers, deposition region dimensions, and layer thicknesses, on temperature and stress distribution. Additionally, the study thoroughly examined the residual stress occurred on the part related to post-cooling and their variations after substrate separation. The outcomes reveal that the dimension of the deposition region significantly impacts both temperature and the size of the melt pool. The melt pool depth of 91 mu m was calculated from the FE models, closely aligning with the experimentally measured value of 84.7 mu m. Furthermore, the separation of the substrate has a notable effect on the distribution of residual stresses in the LPBF specimen. For instance, the residual stress at the center of the first layer decreased from 818 MPa after the cooling process to 108 MPa following substrate separation.