As-deposited Specimens Research Articles

High superelasticity NiTi fabricated by cold metal transfer based wire arc additive manufacturing

NiTi alloy exhibits superior superelastic properties but its wide application is limited by its poor workability. In this study, Ni-rich NiTi wire was used as the feedstock and a wall-shaped NiTi component with height of 130 mm was deposited on Ti substrate by cold metal transfer (CMT) based wire arc additive manufacturing (WAAM) process. The microstructure and mechanical properties of the as-deposited NiTi alloy specimens in the horizontal and vertical directions, as well as their correlations were discussed in detail. In particular, the superelastic properties of the deposited materials were evaluated by cyclic loading-unloading tensile test. It was found that a very high superelastic recovery rate of more than 90% can be reached after 25 cycles for samples tested along both the horizontal and vertical directions. The mechanism that governs the high superelasticity in the alloy was explored in terms of microstructure, chemical composition and phase transformation analyses.

Phase constitution, microstructure and mechanical properties of a Ni-based superalloy specially designed for additive manufacturing

In this study, a kind of Ni-based superalloy specially designed for additive manufacturing (AM) was investigated. Thermo-Calc simulation and differential scanning calorimetry (DSC) analysis were used to determine phases and their transformation temperature. Experimental specimens were prepared by laser metal deposition (LMD) and traditional casting method. Microstructure, phase constitution and mechanical properties of the alloy were characterized by scanning electron microscopy (SEM), transmission scanning electron microscopy (TEM), X-ray diffraction (XRD) and tensile tests. The results show that this alloy contains two basic phases, γ/γ’, in addition to these phases, at least two secondary phases may be present, such as MC carbides and Laves phases. Furthermore, the as-deposited alloy has finer dendrite, its mean primary dendrite arm space (PDAS) is about 30–45 μm, and the average size of γ’ particles is 100–150 nm. However, the dendrite size of the as-cast alloy is much larger and its PDAS is 300–500 μm with secondary and even third dendrite arms. Correspondingly, the alloy displays different tensile behavior with different processing methods, and the as-deposited specimen shows better ultimate tensile stress (1,085.7±51.7 MPa), yield stress (697±19.5 MPa) and elongation (25.8%±2.2%) than that of the as-cast specimen. The differences in mechanical properties of the alloy are due to the different morphology and size of dendrites, γ’, and Laves phase, and the segregation of elements, etc. Such important information would be helpful for alloy application as well as new alloy development.

Hydrogen Diffusion and Trapping in Laser Additively Manufactured Ultra-High Strength AerMet100 Steel

Hydrogen trapping and the permeation behavior of laser additively manufactured (LAM) AerMet100 (UNS K92580) steel with an as-deposited specimen (AD) and after three types of heat-treated specimens (bainite microstructure [BM], tempered bainite and martensite microstructure [TBMM], and tempered martensite [TM]) was investigated. At least three types of different hydrogen traps were identified in each microstructure of the LAM steel, including both reversible and irreversible H traps. For as-deposited microstructure, the main reversible H trap states are related to the precipitation of M3C carbides associated with a detrapping activation energy (Ed) of 17.3±0.2 kJ/mol. After heat treatment, the dominant reversible hydrogen trap states in the tempered martensite microstructure have a different Ed value of 19.3±0.5 kJ/mol, which is attributed to the precipitation of highly coherent M2C carbides. In comparison with the reported Ed value of approximately 21.4 kJ/mol for main reversible hydrogen traps in wrought UNS K92580 steel, the lower Ed value in the LAM steel is closely related to the composition change of M2C carbides. In all of the H precharged samples, the diffusible and total H concentration of the TM specimen and the TBMM specimen are about three to four times higher than that of the AD specimen and the BM specimen. The TM specimen with tempered martensite microstructure has the highest diffusible and total H concentration due to its high density of dominantly reversible H traps. The effective hydrogen diffusion coefficient (Deff) of the LAM steel is on the order of 10−9 cm2/s, and decreases with increasing density of the dominant reversible H traps brought about by heat treatment. The LAM steel has a comparable Deff of about 2.8 × 10−9 cm2/s compared to the wrought steel of a similar yield strength (∼1,750 MPa),

Improvement in corrosion resistance of wire arc additive manufactured Inconel 625 alloy through heat treatment

In this study, an Inconel 625 component was fabricated by gas tungsten arc welding-based additive manufacturing and the as-deposited specimens were heat treated at 980 and 1100 °C for 1.0 h, respectively. The effects of heat treatment on the corrosion resistance and microstructure were investigated. Potentiodynamic polarization tests showed that the as-deposited Inconel 625 alloy had disparities in corrosion resistance compared with wrought Inconel 625 alloy. The corrosion resistance deteriorated after heat treatment at 980 °C due to needle-like δ phases provided more sites to pitting initiation. While the corrosion potential (Ecorr) increased by 32%, passivation current density (Icorr) decreased by 52% after heat treatment at 1100 °C, which was comparable with that of wrought Inconel 625 alloy. Detailed microstructural examination demonstrated the recrystallization occurred with the dissolution of Laves and δ phases, weakening of 〈001〉 orientation, decrease of low angle grain boundaries and formation of large numbers of stable twin grain boundaries. All the evolution of the crystal and microstructure contributed to the striking corrosion resistance of the 1100 °C heat-treated Inconel 625 alloy.

Microstructure and tensile property of a BCC-structured high entropy alloy fabricated by laser melting deposition

The microstructure and tensile property of a BCC-structured high entropy alloy fabricated by laser melting deposition was investigated in this paper. The microstructure of as-deposited specimens was equiaxed grain and consisted of BCC phase and Zr rich precipitate. Due to the in-situ aging effect, the precipitate content in the as-deposited specimen increased with the increase of the distance from the last build plane, which can be weakened by decreasing the input power. With a heat treatment at 950°C for 1h, the precipitate can be completely removed. The strength and ductility of the heat treated specimen were much higher than those of the as-deposited specimen, which may be owing to the increased solution strengthening effect through the dissolution of the precipitates.

Influence of heat treatment on the microstructure and corrosion properties of the Inconel-625 clad deposited by microwave heating

The present work explores the viability of using the microwave heating technique to apply Inconel-625 cladding to a stainless steel (SS-316) substrate. As-deposited clad specimens were subjected to various post-heat-treatments. These treatments included (1) a direct-aged (DA) treatment (2) solution at 981 °C followed by a DA treatment (981SHT) (3) solution at 1081 °C followed by DA treatment (1081SHT). Clad specimens displayed a gradual change in microstructure from planar to cellular to the dendritic depending upon the cooling rate experienced by the molten clad powder during the microwave cladding process. Due to precipitation of hardening particles (γ′), the heat-treated clad specimens displayed superior hardness than as-deposited clad specimen. In the interdendritic spaces/grain boundaries, heat-treatment at 981 °C induces a major reduction in the size of Laves process with a needle precipitation of δ (Ni3Nb) phase. Meanwhile, the heat-treatment at 1081 °C nearly dissolved the entire Laves phase in the microstructure. The corrosion test revealed that the coated samples at all conditions exhibit around 2 to 2.5 times more noble corrosion potential (corrosion resistance) than the uncoated samples. Moreover, the corrosion resistance of the post-treated sample decreases dramatically than that of the as-deposited clad sample, as heat-treatment improved the precipitate phase formation.

Deep Learning-Based Ultrasonic Testing to Evaluate the Porosity of Additively Manufactured Parts with Rough Surfaces

Ultrasonic testing (UT) has been actively studied to evaluate the porosity of additively manufactured parts. Currently, ultrasonic measurements of as-deposited parts with a rough surface remain problematic because the surface lowers the signal-to-noise ratio (SNR) of ultrasonic signals, which degrades the UT performance. In this study, various deep learning (DL) techniques that can effectively extract the features of defects, even from signals with a low SNR, were applied to UT, and their performance in terms of the porosity evaluation of additively manufactured parts with rough surfaces was investigated. Experimentally, the effects of the processing conditions of additive manufacturing on the resulting porosity were first analyzed using both optical and scanning acoustic microscopy. Second, convolutional neural network (CNN), deep neural network, and multi-layer perceptron models were trained using time-domain ultrasonic signals obtained from additively manufactured specimens with various levels of porosity and surface roughness. The experimental results showed that all the models could evaluate porosity accurately, even that of the as-deposited specimens. In particular, the CNN delivered the best performance at 94.5%. However, conventional UT could not be applied because of the low SNR. The generalization performance when using newly manufactured as-deposited specimens was high at 90%.

Effect of Heat Treatment on Microstructure and Properties of 24CrNiMo Alloy Steel Formed by Selective Laser Melting (SLM).

The 24CrNiMo alloy steel powder was used as experimental material. The microstructure and mechanical properties of as-deposited, quenched and tempered (QT) and stress-relief annealed (SR) specimens were analyzed. The X-ray diffraction (XRD) analysis showed that the specimens in the three states were mainly ferrite (α-Fe), in which the as-deposited samples had puny face-centered cubic (FCC) structure Fe (γ-Fe). The microstructure observation showed that the as-deposited specimens were made up of ferrite, granular bainite, a small amount of cementite and residual austenite. The tensile test results indicated that the tensile strength and yield strength of the as-deposited specimens were 1199 MPa and 1053 MPa respectively, and the elongation at break was 10.7%. The elongation of QT and SR specimens increased to 11.6% and 12.8%, respectively. The electron backscattered scattering detection (EBSD) analysis results showed that the small-angle grain boundary content of the as-deposited samples was 58%, and large-angle grain boundary content was 15%. After QT and SR, small-angle and large-angle grain boundaries were obtained than those in the as-deposited specimens. The high-temperature friction and wear properties and thermal fatigue performances of the QT and SR specimens were improved significantly. The QT specimens had the smallest wear and thermal fatigue crack lengths, excellent resistance to friction and wear performance and prevention of crack growth, with an ideal comprehensive properties.

Effect of annealing treatment on the tribological performance of hydrogenated amorphous diamond coatings doped with nitrogen

Pure a-C:H and some nitrogenated coatings (a-C:N:H) with 0.12–2.95 at%N were deposited onto 316 L and Si wafer via the plasma-enhanced chemical deposition (PECVD) technology. Pin-on-ball sliding tests against Al2O3 balls were carried out for as-deposited and annealed coated specimens. The micro-morphology and chemical bonding structure of these coatings with different treatments were characterized using FE-SEM, FTIR, Raman, and XPS. The OH group can be incorporated into the coating bulk, and becomes the active site that reacts with the dangling Al on the counter-body surface to increase the coefficient of friction (CoF), thus gradually increasing the abnormal transition stage occurring in the CoF-sliding time curve. N doping transforms the OH group into NO and CO bonds, and enhances the O/C ratio in the coating to increase the wear rate. Either as as-deposited or an-annealed, the CoF of the pure a-C:H coating always raised with sliding distance, and it was larger than the N-doped coatings. However, the N doped coatings presented higher wear rate. The a-C:N:H coating with 0.12 at% N exhibited the best anti-wear performance, which was with almost the same wear rate as a pure a-C:H coating.

Failure Mechanisms of APS-YSZ-CoNiCrAlY Thermal Barrier Coating Under Isothermal Oxidation and Solid Particle Erosion

The high-temperature oxidation and solid particle erosion of thermal barrier coating (TBC) system which consists of a 8 wt.% yttria-partially stabilized zirconia (YSZ) top coat and CoNiCrAlY bond coat deposited on Inconel 718 substrate via air plasma spraying (APS) process are studied experimentally. Isothermal oxidation tests of the APS-TBCs are conducted at 1050, 1100 and 1150 °C in air for up to 1970 h. Solid particle erosion tests are also performed on both as-deposited and heat-treated APS-TBC specimens at selected particle impingement angles and velocities in room temperature. The scanning electron microscopy (SEM) analyses of the cross sections of the APS-TBC specimens after the oxidation tests show the formation of thermally grown oxide (TGO) scale due to the oxidation of CoNiCrAlY bond coat, and the oxidation kinetics of TGO growth is described by the parabolic rate equation. The failure of the APS-TBC system under isothermal oxidation is associated with the spallation of the top coat through propagation and coalescence of cracks along the coating interface, which is affected by the TGO growth. The solid particle erosion rate of the top coat is found to increase with impingement angle and reach the maximum erosion rate at normal impingement of particles. The erosion resistance of the APS-TBC is observed to increase after the APS-TBC specimen has been exposed at 1100 and 1150 °C for 72 h, probably due to the sintering effect on the top coat, which results in reduction of top coat porosity.

Microstructure and fatigue crack growth behavior of Inconel 718 superalloy manufactured by laser directed energy deposition

In this study, Inconel 718 (IN718) specimens, manufactured by laser directed energy deposition (LDED), are subjected to three different heat-treatments to have different microstructural characteristics. Fatigue crack growth (FCG) testing is performed on both as-deposited and heat-treated specimens. The coarse Laves phases with uneven γ′′/γ′ precipitates severely decrease FCG resistance of LDED IN718. The soft precipitate-free zone around short-acicular δ-phase partly reduces FCG resistance of LDED IN718. The FCG threshold (ΔKth) of a judicious heat-treatment specimen increases by ~ 2.6 times vs. as-deposited specimen and reaches 10.8 MPa∙m1/2, and its ΔKth and FCG curve are comparable to those of wrought IN718.

Microstructures and cyclic hot corrosion behavior of laser deposited Inconel 718 alloy under different heat treatment conditions

In this research, the hot corrosion behavior of laser deposited Inconel 718 alloy under different heat treatment conditions (solution plus aging, direct aging and as-deposited) is investigated in a salt mixture of Na2SO4 (87.5 wt.%) + NaCl (5 wt.%) + NaVO3 (7.5 wt.%) at 650 °C. The weight changes of the Inconel 718 specimens that have experienced different heat treatments are measured during the hot corrosion experiments and the data of the weight changes are used to determine the kinetics of the hot corrosion. Field emission scanning electron microscope (FE-SEM) with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) are employed to characterize the corrosion products of the specimens, thus the corrosion mechanisms are analysed. It is shown that the hot corrosion kinetic of the as-deposited Inconel 718 alloy follows a parabolic law. The element mapping results of the corroded surfaces reveal that the corrosion products of as-deposited Inconel 718 include two distinct layers, of which the outermost layer is mainly composed of Ni2CrO4, Cr2O3 and Fe3O4, while the inner layer contains Ni3S2. The laser deposited Inconel 718 alloys with different heat treatments behave differently in the hot corrosion. The hot corrosion performance of the solution treated specimens is better than that of the directly aged specimens, while the latter has better hot corrosion resistance than the as-deposited specimens. According to the hot corrosion test results and theoretical analyses, the hot corrosion behavior of as-deposited Inconel 718 alloy with different heat treatments in the salt mixture solution is closely related to basic fluxing mechanism, sulphidation and oxidation as well.

Effect of Interlayer Interval Time on the Microstructure and Mechanical Behavior of Additively Manufactured WE43 Mg Alloy

Additive manufacturing of magnesium (Mg) alloys has gained interest for the potential to fabricate complex geometries for extreme light-weighting or improved functionality. In this study, the effect of interlayer interval time and post-deposition processing (i.e., heat treatment and hot isostatic pressing (HIP)) on the microstructure and mechanical behavior of WE43 Mg specimens fabricated by laser powder directed energy deposition (LPDED) was investigated. Microstructure characterization was conducted using optical microscopy, scanning electron microscopy, scanning transmission electron microscopy, and energy dispersive X-ray spectroscopy. Mechanical behavior was evaluated using microhardness and uniaxial tensile testing. Post-processing resulted in improved yield strength, tensile strength, and ductility, which was attributed to a reduction in porosity and, to a lesser extent, the formation of second phase particles. The as-deposited specimens exhibited porosity below 3 pct and HIP treatment reduced porosity to below 0.1 pct. HIP specimens, processed with low interlayer interval time, exhibited the best combination of strength (~ 243 MPa tensile strength) and ductility (~ 9 pct elongation). Changes in interlayer interval time had limited impact on the grain size, hardness, or yield strength. However, increased interlayer interval time (~ 112 pct increase) caused a slight increase in gas porosity and dramatic reduction in tensile strength and ductility, which was attributed to the formation of lack-of-fusion defects in interlayer regions.

Characterization of wire arc additive manufactured products: A comparison between as-deposited and inter-layer cold worked specimens

The presence of large dendrites and alloy segregation in as-deposited wire arc additive manufacturing (WAAM) products results in a wide range of mechanical properties that are often inferior to wrought ones. In this study, the effect of inter-layer cold working on the microstructure and mechanical properties of AISI 347 samples manufactured by WAAM has been investigated. The average hardness of single-pass welding, as-deposited, and cold worked WAAM samples were 190 HV, 249 HV, and 323 HV, respectively. Inter-layer cold working has led to an increase in ultimate tensile strength from 576 MPa to 803 MPa and yield strength from 395 MPa to 697 MPa. Also, Inter-layer cold working and thermal energy due to the deposition of subsequent layers have resulted in microstructural evolution and grain refinement through recrystallization. Besides, a semi-quantitative analysis has shown that increasing the amount of cold working by four times resulted in 64 % decrease in average recrystallized grain size.

Microstructure and Fatigue Crack Growth Behavior of Inconel 718 Superalloy Fabricated Via Laser Directed Energy Deposition Additive Manufacturing

This work investigated the microstructure and its influence on room-temperature fatigue crack growth (FCG) behavior of Inconel 718 (IN718) alloy fabricated with laser-based directed energy deposition (L-DED). As-deposited specimens were heat-treated by direct aging (DA), solution treatment + aging (SA) and homogenization + solution treatment + aging (HSA) respectively to investigate the effect of post-heat-treatment. On comparison with as-deposited microstructure, which mainly consists of γ dendrite and Laves phases in the interdendritic regions. Dendritic segregation still appears after DA heat-treatment, which is certified to alter the precipitation kinetics of γ′′/γ′ precipitations of IN718 and induce the formation of more abundant γ′′/γ′ precipitations in interdendritic Nb-rich regions versus the dendritic trunk regions. After SA heat-treatment, Nb released from the dissolution of Laves phase is prone to diffuse to the ambient interdendritic regions, which facilitates the formation of δ-phase and the homogeneous precipitations of γ′′/γ′ phases in dendritic trunk region. After HSA heat-treatment, the Laves phases are eliminated completely, the dispersive γ′′/γ′ precipitates (~30 nm) are distributed within the bimodal recrystallized grains. The results of FCG testing reveal that as-deposited specimen possesses the lowest threshold for fatigue-crack initiation (ΔKth) and the highest FCG rate (FCGR). The ΔKth and FCGR of DA specimen do not have the notable improvement versus those of as-deposited specimen, due to its inferior strength-plasticity mainly caused by heterogeneous γ′′/γ′ phases and Laves particles. The fatigue-crack propagates easily along the precipitate-free zone around short-acicular δ-phase, which causes the crack branching and deflection, enhances the resistance to FCG of SA specimen to some extent. The ΔKth of HSA specimen increases by ~2.6 times compared with as-deposited specimen and reaches 10.8 MPa∙m1/2, due to its decent strength-plasticity (~1130 MPa, ~26.5%). Especially, the ΔKth and FCGR of HSA specimen are comparable to that of the wrought IN718. The FCG behaviors of all specimens predominantly occur in the transgranular ductile fracture mode. Overall, the present study demonstrates that a judicious post-heat-treatment can enhance the damage tolerance of L-DED IN718 by increasing ΔKth and decreasing FCGR.

Investigation of the bond coat interface topography effect on lifetime, microstructure and mechanical properties of air-plasma sprayed thermal barrier coatings

The effect of bond coat/thermal barrier coating (BC/TBC) interface topography on the lifetime of air-plasma sprayed (APS) TBCs was comprehensively investigated in the present work. A quantitative description of the interface topography was achieved by utilising multiple surface texture parameters obtained from confocal microscopy, including a newly formulated parameter, denominated as total thresholded summit area, Ssth. Thermal cycling fatigue (TCF) testing showed a clear correlation between the TBC lifetime and the interface topography, especially for the novel Ssth parameter. The topographical and microstructural analysis revealed that deposition of a TBC over tortuous BC topographies leads to a highly curved TBC splat morphology, which in turn affected the crack path configuration. Mechanical testing of as-deposited and heat-treated specimens evidenced that the aforementioned microstructural changes promoted a reduced local and global elastic moduli, effectively linking the more compliant TBC microstructures with more beneficial fracture mechanics behaviours and higher TCF lifetimes.

Effects of annealing on microstructure and mechanical properties of γ-TiAl alloy fabricated via laser melting deposition

The microstructure evolution and mechanical properties of the as-deposited γ-TiAl-based alloy specimen fabricated via laser melting deposition and as-annealed specimens at different temperatures were investigated. The results show that the microstructure of as-deposited specimen is composed of fine α2(Ti3Al)+γ lamellae. With the increase of annealing temperature, the bulk γm (TiAl) phase gradually changes from single γ phase to γ phase + acicular α2 phase, finally small γ phase + lamellar α2+γ phase. Compared with the mechanical properties of as-deposited γ-TiAl alloy (tensile strength 469 MPa, elongation 1.1%), after annealing at 1260 °C for 30 min followed by furnace cooling (FC), the room-temperature tensile strength of the specimen is 543.4 MPa and the elongation is 3.7%, which are obviously improved.

Effects of subtransus heat treatments on microstructure features and mechanical properties of wire and arc additive manufactured Ti–6Al–4V alloy

Post heat treatment is necessary to optimize the microstructure of additive manufactured Ti–6Al–4V to satisfy the aeronautical criterion. However, the relationship between the unique heat treated microstructure features and corresponding mechanical properties of wire and arc additive manufactured (WAAMed) Ti–6Al–4V has not been completely understood so far. In this study, five subtransus heat treatment regimes were used to the WAAMed Ti–6Al–4V alloy, and the different heat treated microstructure and the resultant mechanical properties were investigated. The microstructure was not substantially changed after heat treatment 600 °C/4 h/air cooling (AC). The α laths were coarsened after heat treatment 850 °C/2 h/AC, and the higher annealing temperature contributed to the appearance of αs. After solution and aging treatment, there were the discontinuous αGB, coarsened αp, and fine αs. There was the small Widmanstätten structural αs sharing the uniform crystallographic orientation after heat treatment 930 °C/1 h/AC + 550 °C/4 h/AC. The α′ martensite and extremely fine dispersed granular αs were obtained after heat treatment 930 °C/1 h/water quenching (WQ) + 550 °C/4 h/AC. The heat treatment 930 °C/1 h/WQ + 800 °C/2 h/AC was found to be the best heat treatment in this study. The discontinuous αGB, dispersed αs with various crystallographic orientations were obtained, which simultaneously increased the ultimate tensile strength (UTS) and elongation (EL) to 886 ± 8 MPa and 16.6 ± 1.6%, comparing to 847 ± 12 MPa and 12.2 ± 2.8% for the as-deposited specimen. Besides, the α/β interface phase distribution in the as-deposited and heat treated specimens was concerned. Two break-up mechanisms of αp, including boundary splitting and termination migration, were observed and discussed.

Anisotropic tensile behavior of Ti-47Al-2Cr-2Nb alloy fabricated by direct laser deposition

Additive manufacturing is emerging as an increasingly promising technology for TiAl alloys, which are attracting significant attention for their special microstructure and mechanical properties. In the present study, direct laser deposition was applied to fabricate single-track Ti-47Al-2Cr-2Nb alloy walls with a back-and-forth scanning strategy. The resulting alternative-band microstructure, comprising complicated microstructure bands and coarse lamellar colony bands, was characterized, and electronic back-scatter diffraction analysis showed that the lamellae in coarse colonies present a consistent orientation, nearly parallel to the substrate. The tensile properties of the as-deposited specimens varied greatly with the angle (θ) between the loading direction and the substrate. The specimens exhibited the best comprehensive tensile properties of the maximum ultimate strength and elongation (706 MPa and 0.51 %) with the loading direction parallel to the substrate (θ=0°). The ultimate strength and elongation dropped to minimum values of 273 MPa and 0.16 %, respectively, when the loading direction was perpendicular to the substrate (θ=90°). At the middle state of loading direction, θ=45°, the ultimate strength decreased to 358 MPa, and the elongation remained as high as 0.49 %. Transmission electron microscopy observations revealed that dislocations and deformation twinning were both activated under different loading modes, and their morphologies were dramatically different. The formation mechanism of the alternative-band microstructure was proposed from the aspects of rapid solidification and the cyclic heat-treatment effect, and its possible fracture mechanism and crack propagation mode were discussed.

Microstructure and mechanical properties of nano-WC decorated AlSi10Mg composite produced by selective laser melting: effect of heat treatment

Nano-WC and AlSi10Mg composite powder were fabricated by gas-atomised for selective laser melting (SLM). Here, the influence of the heat treatment conditions on microstructure and mechanical properties of WC/AlSi10Mg produced by SLM were investigated, and the mechanisms of microstructure evolution were elucidated. Al substrates are oversaturated, and the solid solubility decreases due to increased annealing temperature. Si particles precipitate from the Al matrix. The mechanical properties of the sample are predominantly governed by the Si particle size. The addition of a small amount of (0.1 wt.%) WC results in tensile strength of 515 MPa in the as-deposited specimen, in comparison with other papers, it was found that significantly enhanced the mechanical properties of the specimen. The results of this study show that adding a small amount of WC and the heat treatment are effective in enhancing the mechanical properties of SLM produced AlSi10Mg samples.