This study evaluates how solution treatment and aging influence the deformation mechanisms, phase transformations and functional performance of NiTi alloys produced by laser powder bed fusion (LPBF). Tensile tests performed at room temperature (RT) and −20 °C (LT) were combined with Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) analyses to correlate mechanical response with transformation thermodynamics and microstructural evolution. In the as-fabricated (AF) condition, deformation is governed by twinning and martensitic plasticity due to suppressed stress-induced martensite (SIM). Solution treatment (ST) restores reversible SIM at RT and preserves partial recoverability at LT as a result of microstructural homogenization and internal stress relief. Aging at 500 °C (A1h, A20h) promotes Ni4Ti3 precipitation, increasing transformation temperatures and stabilizing martensite, which leads to entirely irreversible deformation at both temperatures. These findings establish a clear functional continuum—ranging from recoverable (ST) to dissipative (AF) and fully irreversible (A20h) behavior—and provide a mechanistic framework for tailoring LPBF NiTi components for actuators, energy-storage and energy-dissipation applications.

This study investigates how laser power–scan speed combinations influence densification, surface quality, and mechanical performance of Ti-6Al-4V parts fabricated by Powder Bed Fusion–Laser Beam/Metal (PBF-LB/M) on a DMG MORI LASERTEC 30 SLM (2nd generation) system. A parametric matrix was explored by varying laser power (150–400 W) and scan speed (0.9–1.4 m·s−1) at constant layer thickness and hatch spacing, deliberately omitting contour exposure to isolate core scan effects. A stable processing window was identified (250–300 W; 0.9–1.0 m·s−1) corresponding to ~50–60 J·mm−3 volumetric energy density (VED) achieved at 99.5% with residual porosity of 0.1–0.3%. In this regime, as-built roughness measured Ra = 4–6 µm on top surfaces and Ra = 15–17 µm on side surfaces. Mechanical testing in the as-built showed ultimate tensile strength (UTS) = 1150–1180 MPa and offset yield strength (YS0.2) = 955–994 MPa, with elongation up to 6.7%. Hardness increased from 220 HV to 360 HV as densification improved. Notably, similar VED values derived from distinct power–speed combinations resulted in divergent outcomes, confirming that VED alone does not uniquely predict quality. Comparative benchmarks from the literature data highlight the performance achieved. The resulting process–property map provides a practical reference for parameter optimization, reproducibility evaluation, and transferability across platforms.

The aim of this study is to develop a digital twin hierarchy that fully examines the design and manufacturing processes of an automotive component for metal additive manufacturing. Initially, a lighter model was obtained that was more resistant to static, dynamic, and fatigue loads under various operating conditions. This step improved product strength and resulted in a 28.5% mass reduction. After the product was validated, the orientation of the part direction and the generation of support structures were performed for the manufacturing process. These processes were implemented with the criterion of minimizing production time. Finally, the manufacturing process was digitally implemented using the selective laser melting method and Ti6Al4V material. The design of the experiment was created using the three most frequently preferred values for each of the three important process parameters. After performing process simulations with thermomechanical analyses, Taguchi and ANOVA were applied to the process parameters. The optimum process parameters for layer thickness, hatch spacing, and scanning speed were found to be 30 µm, 50 µm, and 1200 mm/s, respectively.

Functional structures that combine thermal protection with load-bearing capabilities represent an effective solution to hypersonic thermal-protection challenges. Here, we propose a Janus-like bio-inspired strategy for integrally 3D-printed bimetallic metamaterials. Inspired by shell bilayers, a heat-resistant AlSiFeMnNiMg alloy and a SiC-reinforced AlSi10Mg are arranged as an architected pair and fabricated via dual-hopper selective laser melting, with SiC volume fractions of 0, 4, and 8 vol%. In situ SEM tensile tests at 25°C and 250°C show that damage is confined to a narrow transition zone. Once one side softens, the bimetallic architecture redirects load to the other, forming non-percolating high-stress paths and stabilizing the plateau response. Quasi-static compression of Gyroid TPMS lattices with different SiC contents maps the composition-temperature space. Across temperatures, structures with 4 vol% SiC improve specific energy absorption by 11.72% and 18.67% in room temperature and by 10.28% and 18.8% in 250°C, achieving synergistic mechanical improvement and a stable energy-absorbing plateau under extreme environments. Relative to 0 and 8 vol%, where modulus mismatch precipitates premature localized collapse, 4 vol% SiC promotes a distributed shear-band network that delays failure and elevates load capacity. This work provides a practical pathway toward thermally protective and load-bearing integrated components for aerospace applications.

Aim This study evaluated the effects of selective laser melting (SLM), milling, and casting fabrication techniques on surface roughness and screw preload loss of three-unit screw-retained implant-supported Cobalt-Chromium (Co-Cr) frameworks. Methods Ten frame-works were fabricated by each fabrication method (n = 10), and the surface roughness (Ra) was measured using a 3D optical profilometer. The frameworks were torqued to 30 Ncm, retightened after 15 minutes, and subjected to 500,000 cycles in a dual-axis chewing simulator. Pre- and post-load reverse torque values (RTV) were recorded for molar and premolar, and the reverse torque difference (RTD) was calculated. Data were analyzed using ANOVA and Tukey-Kramer tests (α = 0.01). Correlation analyses were performed to determine any relation between surface roughness and preload (RTV and RTD) across all groups. Results Significant differences were found in surface roughness and preload loss among groups (p < 0.01). In molars, the milled group showed the lowest Ra (0.30 µm) and highest post-load RTV (25.2 Ncm), followed by the SLM group (1.73 µm, 20.2 Ncm) and cast group (1.65 µm, 16.9 Ncm). In premolars, the milled group again showed the lowest Ra (0.24 µm) and highest RTV (25.2 Ncm), followed by the SLM group (1.66 µm, 19.4 Ncm) and the cast group (2.57 µm, 17.4 Ncm). There was no significant correlation between roughness and preload loss. Conclusion Different manufacturing technique significantly affects surface topography and screw preload. Milled frameworks showed the least surface roughness and the most torque stability.

Abstract: Selective laser melting (SLM) is considered to be a widely promising additive manufacturing technology with the advantages of high machining precision, high manufacturing freedom, and short cycle time, which is widely used in aerospace, the integration of medicine, and industry, chemical, and other fields. The research progress on the temperature field, stress field, forming quality, and mechanical properties during the SLM manufacturing process is reviewed. The study aims to systematically analyze how SLM process parameters affect the temperature field, stress field, forming quality, and mechanical properties, and to discuss the importance of the selection of process parameters and performance regulation to achieve high-quality, highperformance metal parts. The effects of SLM process parameters on temperature field, stress field, surface roughness, densification, hardness, strength, and fatigue properties are analyzed and summarized. The importance of process parameters in the SLM forming procedure in the quality of formed components is emphasized, and conducting an in-depth study on the optimization and performance regulation of the process parameters is of great significance in achieving the high quality and performance of metal parts. With the rapid advancement of technology, the potential of SLM technology in terms of molding quality and mechanical performance has become increasingly significant, heralding significant breakthroughs. These potential breakthroughs will greatly promote the widespread application of SLM technology in various industries, thus more efficiently meeting the growing needs and expectations of industries such as petrochemicals, transportation, aerospace, nuclear energy, as well as food and medical sectors.

In this study, 3 wt.% Re/Inconel 718 composite was fabricated by laser powder bed fusion (LPBF), and the effects of aging treatments on the microstructure and properties of the Re/Inconel 718 composite were systematically investigated. This study aims to elucidate the synergistic optimization of microstructure and properties in LPBF Inconel 718, achieved through Re alloying and subsequent heat treatment. Results demonstrated that the samples undergo recrystallization and precipitate numerous fine strengthening phases after heat treatment. Concurrently, heat treatment promotes the diffusion of Re within the material, leading to a significant reduction in its concentration in locally enriched regions. The addition of Re improves the mechanical properties and corrosion resistance of the Inconel 718 alloy through synergistic strengthening mechanisms, including dispersion strengthening, solid solution strengthening, and dislocation strengthening. When the two-stage aging is 720 °C × 8 h (FC × 2 h) + 620 °C × 8 h (AC), the optimum mechanical properties are observed. The dissolution of Laves phases, simultaneous precipitation of both γ″ and γ′ phases, and homogenization of microstructure are responsible for the enhancement of the material’s mechanical properties. However, the extensive precipitation of strengthening phases also promotes the formation of numerous microscopic corrosion cells, which accelerates the corrosion rate and leads to a marked reduction in corrosion resistance of the material. This study provides new insights into the laser additive manufacturing of high-performance nickel-based composites.

Enhanced strength and ductility in aluminum alloys produced by laser powder bed fusion: Tunable nano-precipitates effect via copper addition

A powder-bed in-situ modification strategy for surface quality enhancement in laser powder bed fusion: A case study on oxide ceramics

Simultaneous Strength and Ductility Enhancement in In-situ Alloying Ti6Al4V Alloy by Trace Carbon Addition via Laser Powder Bed Fusion (LPBF)

Influence of annealing and tempering on the wear and corrosion behavior of WC/W2C reinforced composites fabricated by laser powder bed fusion

Numerical study of the transport behavior and deposition pattern of large spatter particles in laser powder bed fusion via CFD-DPM modeling and optimization of spatter control strategies

Effect of layer thickness on the microstructure and machinability of AlSi7Mg processed by laser powder bed fusion

Bio-inspired additive texturing of Ti-6Al-4V using laser powder bed fusion and its feasibility analysis for biomedical applications

Effect of substrate preheating on microstructure and mechanical properties of AlSi10Mg alloy manufactured by laser powder bed fusion

Abstract The creep response of AISI 316L austenitic stainless steel produced by additive manufacturing has garnered considerable attention in recent years. This interest stems from the unique microstructure created by the exceptionally high cooling rates characteristic of this technology. Despite numerous studies addressing this issue, the constitutive analysis of the relationships between temperature, stress, and creep response has predominantly relied on traditional phenomenological models, which do not facilitate an easy quantitative correlation with microstructural features. The primary objective of this study was to bridge this knowledge gap by proposing a physically based constitutive model that elucidates the unique dependence of the minimum creep rate on applied stress and temperature in AISI 316L steels manufactured through additive processes. The short-term creep behavior of AISI 316L stainless steel fabricated by the laser powder bed fusion additive manufacturing technology was investigated at 600 and 650 °C, using constant load and variable load experiments. The microstructure was characterized by transmission electron microscopy; fracture analysis was performed on crept samples by scanning electron microscopy. Creep response was compared to literature concerning other 316L stainless steel samples fabricated by the same additive manufacturing technology and to conventional wrought steels having a similar composition. Results showed comparable time to ruptures, although the steel investigated in the present study showed much lower (one order of magnitude) minimum creep rates. The microstructural results suggested assimilating the steel to a purposedly developed simplified model-material. Combination with available constitutive models confirmed the strong relationship between creep behavior and microstructural features. Graphical Abstract

Comparing geometry and mechanical performance of as built and Hirtisation® treated Al-Cu-Mg-Ag-Ti-B-Si-Fe rhombic dodecahedron lattices manufactured by laser powder bed fusion

Retraction notice to “The role of defect structure and residual stress on fatigue failure mechanisms of Ti-6Al-4V manufactured via laser powder bed fusion: Effect of process parameters and geometrical factors” [Journal of Manufacturing Processes 102 (2023) 549–563

Microstructural characteristics and mechanical properties of 316L SS/316L SS-xTi6Al4V disordered gradient layered structures based on laser powder bed fusion

A new additive manufacturing factor dominating porosity and mechanical performance of alloys via laser powder bed fusion