ABSTRACT This study aims to enhance the high-temperature mechanical properties of the laser-directed energy-deposited Inconel 625 alloy. Varied sizes, morphologies and volume fractions of the Laves phase were effectively regulated, high-temperature tensile properties and stress rupture life were systematically investigated, and the underlying mechanisms were revealed thoroughly. The results demonstrate that when the Laves phase morphology transitions from long-striped to granular, with optimised dimensions (length: 1–2 μm, width: 0.2–0.6 μm) and a precise volume fraction of 1.2%, the alloy exhibits a notable enhancement in mechanical performance: yield strength increases from 192.67 MPa to 217.33 MPa, tensile strength rises from 324.67 MPa to 348.33 MPa and stress rupture life extends from 24 h to 31 h. The boost in the high-temperature tensile strength was attributed to the precipitation of γ'' and δ phases near the Laves phase or the pinning effect at the Laves/γ interface. The extended stress rupture life results from δ phases hindering dislocation motion while promoting dynamic recovery. This study confirmed that retaining a controlled amount of Laves phase significantly enhances the mechanical properties of the Inconel 625 alloy, providing valuable insights for laser additive manufacturing and repaired nickel-based superalloy above 800°C.

Ti3C2Tx-enhanced photo-thermoelectric performance of Bi2Te3 in scaffold for improved osteogenic potential.

Intergranular solidification defects in high-strength 2A14 aluminum alloy fabricated by laser additive manufacturing: Role of secondary phases

Effect of BN whisker addition on the microstructures and thermo-mechanical properties of Al-36Si-3Cu-5Mg alloy fabricated via laser additive manufacturing

The formation characteristics analysis of cladding layer in the laser additive manufacturing on inclined substrate under the different scanning speed conditions

Advances, challenges and prospects in one-step preparation of melt-grown Al2O3-based eutectic in-situ composite ceramics by laser additive manufacturing

Equiaxed dendrites formation and anisotropy control of high Nb-TiAl alloy by laser additive manufacturing with water-bathed environment

In-situ laser additive manufacturing of bimetallic alloys with steel-clad copper-core wire

2319 Al alloy fabricated by a novel pre-melted liquid filler laser additive manufacturing: Porosity, microstructure, and mechanical property

Bio-resin can be altered to experience chemical activation using a range of visible wavelength light sources, paving the way for an environment friendly resin curing mechanism with a potential application for additive manufacturing technology. Currently, additive manufacturing utilizes petroleum-based resins activated with an ultraviolet light source. In this experimental investigation, a tung oil-based bio-resin is used to examine how visible wavelength lasers cure resin only in localized areas either on surface or in subsurface and what parameters can be considered for process optimization. Additionally, experimental results are reported to observe the impact of color additives on the curing rate of the resin. Three different visible wavelength lasers are used for conducting the curing process—405, 450, and 532 nm. The lasers run at their maximum power as well as equivalent energy density to observe their performances on the curing process. On the other hand, two types of initiators and two types of energy-absorbing pigment additives are mixed in combination to find out which combination improves the curing process the most. Trials are carried out on both base resin and additive-mixed resins to observe the effects of the additives. While both surface and subsurface curing of base resin is observed using 450 nm wavelength laser exposure, subsurface curing of additive-mixed resin is observed using 405 and 532 nm wavelength lasers. The tunability of these tung-oil based resins makes them attractive candidates for further research for numerous laser additive manufacturing processes.

The Zn-3Mg alloy fabricated by laser powder bed fusion (LPBF) additive manufacturing is widely used in biomedical implants due to its excellent biocompatibility and favorable mechanical strength. However, its application is hindered by limited ductility and a relatively rapid degradation rate. This study investigated the influence of annealing heat treatment on the microstructure, mechanical properties, and degradation behavior of LPBF-fabricated Zn-3Mg porous implants. A systematic analysis of various annealing parameters revealed the evolution mechanisms of the microstructure, including grain coarsening and the precipitation and distribution of secondary phases Mg2Zn11 and MgZn2. The results indicated that appropriate annealing conditions (such as 250 °C for 1 h) significantly enhanced the compressive strain by 10%, while maintaining a high compressive strength of 24.72 MPa. In contrast, excessive annealing temperatures (e.g., 365 °C) promoted the formation of continuous brittle phases along grain boundaries, leading to deterioration in mechanical performance. The degradation behavior analysis illustrated a substantial increase in the corrosion rates from 0.6973 mm/year to 1.00165 mm/year after annealing at 250 °C for 0.5 h and 365 °C for 1 h, which can be attributed to the micro-galvanic effect induced by the presence of fine or coarse secondary phases that promoted localized corrosion. This study demonstrated synergistic regulation of mechanical properties and degradation behavior in the Zn-3Mg porous structures through optimized heat treatment, thereby providing essential theoretical and experimental supports for the clinical application of biodegradable zinc-based implants.

Microstructure and properties of graphene/AlCoCrFeTiCux coatings fabricated by laser additive manufacturing

Lightweight Al alloys with enhanced mechanical properties are essential for structural applications across various industries. To promote sustainable material flow, this study introduces an Al-Fe-based multi-elemental alloy series optimized for laser-based additive manufacturing (AM) using powder bed fusion (PBF-LB), leveraging recycling-friendly Al alloys with Fe as a major impurity. The alloy design is based on the concept of elemental partitioning into either the liquid phase (forming metastable Al6Fe phase for strengthening) or the solid phase (α-Al matrix) during solidification. Investigations of PBF-LB processed Al-Fe-X ternary alloys (X: Cu, Mn, and Ti) reveal the distinct roles of these alloying elements: Cu and Mn stabilize the Al6Fe phase, while Ti enhances solid-solution strengthening, in the microstructure and associated mechanical properties. Additionally, Ti promotes grain refinement by inducing the heterogeneous nucleation of nanosized Al3Ti-phase particles, leading to improved material ductility. The combined addition of alloy elements further stabilizes and strengthens the Al6Fe phase (Cu and Mn). Moreover, Mn and Ti partition independently, enabling precise control of the α-Al/Al6Fe two-phase microstructure, enhancing high-temperature mechanical performance. This study provides new insights for controlling refined metastable phases formed via PBF-LB, facilitating the development of high-performance, sustainable Al alloys for AM technologies.

Additive manufacturing (AM) addresses the challenges faced by traditional manufacturing techniques in terms of cost, time and machinability. It is gradually advancing toward higher precision and smaller sizes, particularly at the micrometer scale where the limits are much tighter than in macro manufacturing. Laser microadditive manufacturing (LMAM) offers unmatched high precision and flexibility compared to macroscopic AM methods (up to tens of micrometers). Therefore, LMAM technologies have shown great potential in the manufacturing of customized, miniaturized components and high-performance materials. They have broad application prospects in aerospace, medical devices, electronic components, mold manufacturing and microelectromechanical systems (MEMS). However, there is currently no established LMAM solution for conductive microstructures at small scales. To address the issues related to finite resolution and conductivity of transparent substrate surfaces, various new LMAM technologies are being developed for micrometer/nanometer scale conductive structures. This paper reviews the efforts made so far with a focus on laser additive manufacturing (LAM), laser-induced transfer (LIT), laser-induced chemical deposition (LICD), and laser electrochemical composite deposition (LECD) technologies. Importantly, this paper provides a detailed analysis of LMAM technologies and their unique implications while comparing the potential of current LMAM technologies for conductive microstructures. Finally, it discusses improvement measures in the LMAM process and suggests future research work.

Effect of pulse frequency on the structure and properties of TC11 alloy prepared by laser additive manufacturing

Densification, microstructure, crystallographic texture and mechanical properties in increased productivity laser additive manufacturing of pure tantalum

Influence of active elemental sulfur on elemental mixing and concentration distribution in laser additive manufacturing processes

Abstract In the context of Industry 4.0, advanced manufacturing technology continues to innovate, and laser additive manufacturing technology has ushered in opportunities for development. However, it also faces many challenges, among which precise control of the dynamic interaction between high-energy lasers and metal materials is the core problem. The surface of the melt pool fluctuates under the action of metal vapor recoil pressure, loses its stable state, forms keyholes, and then produces pore defects, which become a key factor affecting the quality stability of formed materials. To achieve the relevant research objectives, an experimental platform with adjustable gas parameters was built. Air was selected as the blowing gas, and the initial temperature of the metal liquid surface was set as the only variable when the blowing angle, distance, and wind speed were kept fixed. With the help of high-speed dynamic imaging technology, the fluctuation patterns of the molten pool surface under different temperature conditions were captured, and the evolution characteristics of the keyhole morphology were obtained.

This literature review examines recent advancements in Shape Memory Alloy (SMA)–based honeycomb and cellular morphing structures for adaptive aerodynamic surfaces, with research spanning from 2018 to 2025. Special emphasis is placed on inverse morphing design methodologies, compliant structural mechanisms, selective laser melted SMA lattices, and thermalmechanical actuation strategies enabling continuous, hinge-less deformation for wings and control surfaces. SMA honeycomb actuators have emerged as a lightweight and compact solution capable of achieving significant deformation amplitudes, high actuation strain recovery, and embedded smart functionality suitable for small-scale unmanned aerial vehicles (UAVs), micro air vehicles (MAVs), and experimental adaptive wings. Studies demonstrate that SMA-integrated honeycomb structures provide smooth camber variation, trailing-edge deflection, and active twist control while retaining structural stability and aerodynamic continuity. Across the reviewed works, several important themes arise: (i) The development of inverse design frameworks to determine optimal SMA placement for achieving target aerodynamic shapes, (ii) The increasing use of selective laser melting (SLM) and additive manufacturing for fabricating complex SMA micro-lattices, (iii) improved Multiphysics modelling approaches that couple thermal activation, phase transformation, honeycomb deformation mechanics, and aerodynamic loading, and (iv) experimental validation of morphing prototypes for trailing-edge devices and adaptive airfoils. Benefits include enhanced lift coefficients at low speeds, drag reduction through smooth camber control, improved gust response, and increased adaptability across multiple flight regimes. However, limitations persist, including slow SMA cooling rates, nonlinear hysteresis, high energy consumption for repeated actuation, and structural fatigue concerns. This review synthesizes findings across 15 major studies to identify current capabilities, comparative methodologies, emerging challenges, and future pathways for SMA honeycomb–based adaptive flight technologies. The collective analysis highlights the growing maturity of SMA morphing concepts and underscores the potential for fully integrated, sensor-driven adaptive wings designed through inverse-design optimization and validated through coupled Multiphysics simulations and experiments. The report concludes by outlining the next steps required to transition SMA honeycomb morphing systems from laboratory demonstrators to field-deployable systems for UAVs and future aircraft

Samples of H13 tool steel were produced using the LENS® laser additive manufacturing technique. Three variants of samples were produced such that during and 2 h after deposition, both the substrate and sample temperatures were maintained at 80, 180, and 350 °C. After the samples were produced, the effect of the substrate temperature on their metallurgical quality, microstructure, and mechanical properties was determined. No segregation of alloying elements was observed. The test results indicate that, depending on the temperature used, the structure of the H13 alloy is martensitic or martensitic-bainitic with a slight residual austenite content of up to 2.1%. Owing to structural changes, the obtained alloy is characterized by lower impact strength compared with conventionally produced alloys and high brittleness, particularly when using an annealing temperature of 350 °C. Isothermal annealing above the martensite start temperature results in extreme brittleness due to a partial structural transformation of martensite into bainite and probable carbide precipitation processes at the nanoscale.