Based on the combination of the basic theory of first principles and experiments, this study investigated the influence of Cr doping on the phase transformation temperature and magnetic properties of Ni-Co-Mn-In magnetic shape memory alloys. Due to the fact that the radius and electronic structure of Cr atoms are similar to those of Mn, and according to the law of the lowest energy, the energy of Cr replacing Mn is the lowest, the Cr replacing Mn site is mainly studied. Through the electron-orbital hybridization effect, the total magnetic moment is jointly reduced. By observing the density of states, it is known that the addition of Cr has a certain improvement on the stability of both austenite and martensite. Meanwhile, through first-principles simulation, it is known that with the increase of Cr content, the Curie temperature (TC) and martensitic transformation temperature show a slight downward trend. And as Cr increases, it is directly proportional to the stability of austenite. Ni45Co5Mn37.5-xIn12.5Crx (x=0, 1, 2at%) was prepared by vacuum arc melting furnace. The research found that an appropriate amount of Cr (x=1) doping led to a decrease in the martensitic transformation temperature (TM). Excessive doping of Cr (x=2) will cause the energy difference (Δ EMA) between austenite and martensite to have A decreasing tendency. The TM was found to be 376 K when the Cr doping amount was 0 At. %, and 347 K when the Cr doping amount was 1 At. %, which was 29K lower than that without doping. Moreover, when the Cr doping amounts were 2 At. % and 3 At. %, the martensitic transformation would produce an unstable state. When doped with 3at.% Cr, the Curie temperature of austenite is 368K, and when doped with 1at.%, it is 38 K. The austenite Curie temperature of 3at.%Cr doped was 16K lower than that of 1at.%, and it was 22K lower than that of 390K without Cr doping. It can be seen that the doping of Cr will reduce the Curie temperature, which is consistent with the simulation.

Using slow cooling and re-dissolution after solution treatment, this study systematically investigates the effects of four heat treatment processes on the γ′ phase, grain boundary morphology, and tensile properties at 650 ℃ of a nickel-based cast superalloy. The results show that the slow cooling process induces the formation of chain-like irregular γ′ phases at the alloy’s grain boundaries. It promotes the transformation of straight grain boundaries into serrated ones, significantly improving the material’s medium-temperature brittleness. However, the intragranular precipitation of coarse flower-like γ′ phase reduces the yield strength. The high-temperature short-time re-solution process completely dissolves the γ′ phases formed by prior slow cooling. It restores serrated grain boundaries back to straight ones, leading the alloy to exhibit brittle characteristics again. The low-temperature long-time re-solution process achieves synergistic optimization of the alloy’s γ′ phase and grain boundary morphology. It retains serrated grain boundaries to maintain grain boundary strength, while reshaping coarse flower-like γ′ phases into medium-sized near-spherical particles, which further optimizes the balance between medium-temperature strength and plasticity. This study reveals the positive effect of serrated grain boundaries on improving the alloy’s medium-temperature tensile properties. It provides a theoretical basis and technical reference for the optimization of heat treatment processes for nickel-based superalloys.

NiTi alloy has garnered significant attention due to its unique functional properties, and laser powder bed fusion has become the mainstream additive manufacturing technique for producing NiTi alloy components. However, the surface roughness of as-fabricated parts is generally too high to permit direct assembly and application, and it is difficult to reduce via conventional machining. Laser remelting, as a non-contact surface treatment technique, can modify the surface morphology and microstructure of materials. This work aims to reduce the surface roughness of NiTi alloy fabricated by laser powder bed fusion through laser remelting, and to elucidate its effects on the mechanical and functional properties of the alloy. Based on experimental data, a regression equation relating the laser remelting process parameters to surface roughness is established. The optimal parameter combination is determined through response surface optimization. The differences in mechanical properties and superelasticity of the alloy before and after laser remelting are evaluated, and the underlying mechanisms are analyzed via microstructure characterization. The results show that the optimal parameter combination for laser remelting is a defocusing distance of 175 mm, a spot diameter of 0.1 mm, a pulse frequency of 250 MHz, a laser power of 60.2 W, and a scanning speed of 1966.4 mm/s. After remelting, the roughness of the alloy decreased from 8.04 μm to 0.763 μm, the tensile strength increased from 588 MPa to 656 MPa, and the stable recoverable strain in tensile superelasticity improves from 2.1% to 2.8%. The enhancement in strength can be primarily attributed to grain refinement in the remelted surface layer, while the improved superelastic stability and recoverable strain result from the synergistic effects of grain refinement and the precipitation of Ti2Ni phase.

Surface-enhanced Raman spectroscopy (SERS) has emerged as a pivotal analytical technique in biomedical and environmental monitoring due to its ultra-high sensitivity and molecular fingerprint specificity. However, conventional metallic substrates (e.g., colloidal Au/Ag) face limitations such as high fabrication costs, poor signal reproducibility, and insufficient biocompatibility. Two-dimensional materials (2DMs), as a new generation of SERS substrates, are progressively overcoming these performance bottlenecks by virtue of their unique properties, including atomically flat surfaces, strong fluorescence quenching capability, tunable electronic structures, and layered architecture with atomic-level thickness. Benefiting from abundant surface dangling bonds, defect sites, and highly active planes, 2DMs enable an enhancement pathway dominated by the chemical mechanism (CM), achieving CM enhancement factors as high as 10²-10³. This can synergize with the electromagnetic mechanism (EM), while maintaining excellent biocompatibility and chemical stability, thereby providing an ideal platform for single-molecule detection, in vivo imaging, and in situ monitoring of interfacial catalytic reactions. This review summarizes recent domestic and international advances in the mechanistic understanding and applications of 2DMs, synthesizes the relationships between material structure, SERS enhancement mechanisms, and modulation strategies, and highlights relevant achievements in areas such as pesticide residue detection and biomarker analysis. Current research challenges are discussed, and future research directions are outlined.

Magnesium (Mg) alloys have garnered significant attention as promising green engineering materials for the 21st century, owing to their low density, high specific strength, and excellent damping capacity. Meanwhile, additive manufacturing (3D printing), as an emerging advanced fabrication method, exhibits unique advantages in efficient forming and high-performance component production, particularly for complex structural parts. Mg alloy additive manufacturing technology demonstrates broad application prospects in fields such as biomedical implants, aerospace components, and automotive lightweighting. This review focuses on three mainstream Mg alloy additive manufacturing techniques: selective laser melting (SLM), wire arc additive manufacturing (WAAM), and friction stir additive manufacturing (FSAM). It systematically summarizes and analyzes recent research progress in microstructural characteristics, mechanical properties, and corrosion behavior. Finally, the future development directions and technological trends for these three technologies are outlined.

Titanium alloys are widely used in aerospace, energy, and biomedical engineering owing to their high specific strength, excellent corrosion resistance, and good thermal stability. The service performance of these alloys is strongly governed by their microstructures and the associated evolution mechanisms. This review provides a comprehensive summary of recent advances in microstructure control and mechanical property optimization of high-strength and high-toughness titanium alloys, with particular emphasis on α↔β phase transformation, metastable phase transitions, and multi-scale microstructure evolution. Existing studies reveal that microstructural architectures play a critical role in strength-toughness balancing: nanocrystalline structures markedly enhance yield strength, whereas gradient and heterogeneous structures can improve high-cycle fatigue life by several times. The key contributions of additive manufacturing, thermo-mechanical coupling treatments, and metastable phase-induced plasticity in overcoming the conventional strength-ductility trade-off are also highlighted. In addition, emerging data-driven and machine-learning-based methods are enabling rapid prediction of composition- microstructure- property relationships and accelerating the intelligent design of titanium alloys. Finally, future research directions are proposed concerning dynamic microstructure evolution under multi-field coupling, cross-scale mechanism modeling, and the stable fabrication of large-scale components. This review aims to provide systematic insights and development guidelines for the microstructure design and performance optimization of advanced high-strength and high-toughness titanium alloys.

Sulfide solid-state electrolytes have emerged as ideal candidates for constructing high-energy-density all-solid-state lithium batteries (ASSLBs), owing to their room-temperature ionic conductivity comparable to that of liquid electrolytes and exceptional cold-pressing processability. However, the solid-solid interfacial compatibility issues between sulfide electrolytes and electrode materials constitute a critical bottleneck impeding the commercialization of this system. This review systematically dissects the key interfacial challenges in sulfide-based ASSLBs, including physical contact loss, interfacial side reactions, space-charge layer effects, and lithium dendrite growth, while revealing their multiscale coupling mechanisms. This article provides a systematic overview of recent advances in interfacial optimization strategies, with a focused discussion on modifications pertaining to the cathode, electrolyte, and anode. Finally, we provide perspectives on future research directions, emphasizing that multi-scale and multi-dimensional synergistic innovation is crucial to realizing high-performance and safe sulfide-based ASSLBs. Future studies should dedicate efforts to unraveling the multi-physics coupling mechanisms and advancing the cross-scale synergistic design of “material-interface-structure”, thereby accelerating the transition of sulfide-based ASSLBs from material innovation to practical engineering application.

Among the existing iron-based heat-resistant materials, austenitic heat-resistant steel has excellent high-temperature strength, creep resistance and favorable oxidation resistance, thus finding extensive application in high-temperature structural components such as nuclear reactors and automobile engines. As the service temperature of materials continues to rise, higher demands have been placed on their high-temperature performance. Austenitic heat-resistant stainless steel achieves solution strengthening and precipitation strengthening through the addition of alloying elements such as Nb, V, and W. Within its microstructure, precipitated phases including MX, M₂₃C₆, and Z phases are formed, which collectively enhance the high-temperature tensile properties and creep performance of the alloy. Additionally, elements like Cr and Al are utilized to improve the alloy's oxidation resistance. In this paper, the development status of austenitic heat-resistant steel is reviewed. Its influence on high-temperature mechanical properties is analyzed from the perspectives of composition, elemental effects, and microstructural characteristics. Additionally, the steel's high-temperature tensile properties, creep properties, oxidation resistance, and their influencing factors are elaborated. Finally, the future research directions of austenitic heat-resistant steel are prospected.

This study presents a method for preparing spherical polylactic acid (PLA) powder based on thermally induced phase separation (TIPS). By controlling PLA concentration and cooling rate, the solution system is confined within the metastable region to achieve stable phase separation into spherical droplets via the nucleation and growth mechanism. The effects of stirring rate and spheroidization time on powder characteristics, including morphology and particle size, are systematically investigated, with consideration of the concomitant processes of Ostwald ripening and droplet coalescence. The powder exhibits an angle of repose ranging between 28.37° and 39.95°, indicating high flowability that meets the requirements of laser powder bed fusion (LPBF). Additively manufactured PLA parts demonstrate a tensile strength of 36.87 MPa, a flexural strength of 52.51 MPa, and compressive strength of 22.14 MPa for triply periodic minimal surface scaffolds. These results confirm the excellent processability of the PLA powder in the LPBF process and establishe both theoretical and technical foundations for advancing the application of LPBF in fabricating complex PLA structures.

Nickel-based superalloys are widely used in key components such as aero-engine combustion chamber casings owing to their excellent high temperature performance. K439B nickel-based alloy is a novel high-temperature material capable of operating at 800℃, which has potential for further enhancing aerospace engine performance. However, traditional casting process struggles to meet the high requirements for thin-walled, complex components. In this study, LPBF technology was uesd to process samples. By adjusting the laser power (140–220 W) and scanning speed (600-1400 mm/s), and using characterization techniques including optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD), the effects of process parameters of LPBF on the relative density and microstructure were analyzed. The processing window for manufacturing K439B superalloy via LPBF was summarized, and two parameters within the window were selected to process samples for tensile tests at room-temperature and 800°C. The results showed irregular pores and Ti-C carbides were prone to form under the 160W-1000mm/s (VED = 66.67 J/mm³) parameter. In contrast, the samples processed under 220W-1200mm/s (VED = 114.58 J/mm³) had a uniform microstructure without carbides; whose ultimate tensile strength at room temperature was over 1 GPa and elongation was over 25%. However, at 800°C, all LPBF samples exhibited brittleness (with an elongation after fracture of approximately 0.5%), which was mainly attributed to the lack of γ' phases and the precipitation of M23C6 that weakened the grain boundaries.

Mg-air batteries have garnered significant attention in recent years due to their outstanding advantages, including high theoretical energy density, excellent safety, low cost, and environmental friendliness. However, systematic reviews concerning aqueous Mg-air battery electrolytes remain relatively scarce. The Mg anode is prone to self-corrosion, discharge product accumulation, and severe block effect in aqueous environments. This results in low anode utilisation, suboptimal operating voltages, and pronounced voltage fluctuations, making the electrolyte a critical factor constraining the practical application of Mg -air batteries. To address this, this paper systematically reviews the fundamental properties and key influencing factors of aqueous Mg -air electrolytes, focusing on electrolyte system selection, interfacial control strategies, and additive mechanisms. The review covers the structural characteristics and applicability of chlorinated and chlorine-free near-neutral electrolytes, the regulatory roles of inorganic, organic, and composite additives, and the synergistic effects of anions at the electrolyte/anode interface. Finally, future development directions for aqueous Mg -air electrolytes are proposed, including deepening the understanding of interfacial regulation mechanisms, green design of electrolyte systems, and rapid formulation screening based on machine learning. This paper aims to provide reference for the research and application of high-performance Mg -air battery electrolytes.

Solid oxide fuel cell (SOFC) is a green and efficient electrochemical energy conversion device. Due to the use of solid ceramics as electrolyte materials, it needs to work in a high temperature environment of 600-1000℃. The high temperature environment can accelerate the aging of equipment materials, resulting in the rapid decline of battery performance. Intermediate and low temperature SOFC technology can improve the startup speed of the system, improve the durability of the equipment, and expand the scope of equipment selection. Therefore, the development of intermediate and low-temperature SOFC technology is crucial to achieve its commercial application. Since charge transfer and oxygen exchange reactions in solid electrolytes are thermal activation processes, the decrease of SOFC operating temperature can increase the ohmic polarization of the electrolyte and increase the polarization loss of the electrode, which can affect the actual power of SOFC. In recent years, the research of SOFC technology at intermediate and low temperature has mainly focused on optimizing the microstructure and chemical composition of electrodes and electrolyte materials. In this work, the research progress on the SOFC key materials for electrode and electrolyte to intermediate and low temperature is systematically summarized, and the future design and development direction of SOFC key materials are prospected.

Environmental barrier coatings (EBCs) are a key protective technology for the ceramic matrix composites (CMCs) hot end components of high-performance aircraft engine, which can significantly improve the service stability and reliability of the components. In this paper, Si/Yb2Si2O7/Yb2SiO5 tri-layer structural EBCs are prepared by air plasma spray (APS) and their corrosion behavior and degradation mechanism under 1350 ℃ and cycling water vapor conditions are investigated. The results show that the as-annealed coating is mainly composed of monoclinic Yb2SiO5 phase and cubic Yb2O3 phase, with nano-sized Yb2O3 phase disperses in Yb2SiO5. The surface of Yb2SiO5 coating exhibits a ridge-like structure accompanied by a certain number of pores after cyclic water vapor corrosion, and the content of corrosion products Yb2Si2O7 increases with the number of cycles. The formation of Yb2Si2O7 is related to the alternating wet to dry corrosive environment and the gaseous substance Si(OH)4. Penetrating cracks exists within the Yb2SiO5 coating but terminates at the Yb2SiO5/Yb2Si2O7 interface, and the SiO2 film generated from the oxidation of the Si bond coat is well bonded to the Yb2Si2O7 interlayer and the Si bond coat in general. The tri-layer EBCs system in this paper exhibits excellent resistance to cyclic water vapor corrosion at 1350 ℃.

A new type of Ni-20W-20Cr heterogeneous seed with low melting point, low segregation, and cellular branching characteristics was designed by Pandat thermodynamic software combined with high-throughput experimental method using Ni-20W binary alloy as the base alloy. DSC results showed that the temperature of the solid and liquid line for Ni-20W-20Cr heterogeneous seed were 1399.7 ℃ and 1419.1 ℃, respectively. Compared with the traditional seed, it existed a narrow solidification interval as 19.4 ℃. In addition, the primary spacing of the Ni-20W-20Cr heterogeneous seed during the growth was also calculated. The results showed that the primary spacing had experienced a first increasing and then decreasing process, which was in good agreement with the KF model (111±8.37μm→116±4.77μm→125±6.41μm→105±3.65μm). After that, based on the interface instability model, the transition rate for the flat interfacial instability and the cellular branching were calculated. The results showed that the flat interfacial instability transition rate in the experiment matched the model well, but the cellular branching transition rate in the experiment was higher than that in the model, which indicated that the traditional primary spacing model might not be suitable for the step incremental speed experiment. At the same time, the EDS results showed that the Cr elements were mainly concentrated on the inter-dendrites, and W elements were enriched in the dendritic stem, while Ni element was basically even distributed. At last, Ni-20W-20Cr heterogeneous seed with a cellular-dendritic structure was prepared. And it was proved that the Ni-20W-20Cr heterogeneous seed could be re-used during the preparing of the single crystal blades.

Nanomaterials with combined photothermal-chemodynamic therapy (PTT-CDT) offer significant advantages in cancer treatment, yet designing and fabricating such multifunctional nanomaterials remains challenging. In this study, cuttlefish ink (M) was used as a core, onto which a layer of CuO was grown, successfully constructing the M@CuO composite multifunctional nanomaterial. The M@CuO exhibited a spherical shape with a nanoparticle size of 128.2 nm and demonstrated excellent photothermal conversion efficiency (ηT = 47.6%) under near-infrared (NIR) light irradiation. Additionally, the M@CuO showed a strong Fenton effect at room temperature (25°C), and the Fenton reaction rate could be further enhanced by the photothermal effect, with the reaction rate at 45°C being 2.3 times that at 25°C under the same conditions.In vitro cell experiments reveal that M@CuO had good biocompatibility and could effectively kill tumor cells through combined PTT-CDT. Therefore, M@CuO provided an effective strategy for developing multifunctional nanomaterials with PTT-CDT synergistic therapy.

This paper aims to compare the changes in residual flexural strength after surface damage in chemically strengthened lithium aluminosilicate glass and chemically strengthened aluminosilicate glass. The single-particle sandblasting damage and multi-particle sandblasting damage of chemically strengthened lithium aluminosilicate glass and chemically strengthened aluminosilicate glass were prefabricated by a self-made sandblasting tester at different pressures. The bending strength before sandblasting and residual flexural strength after sandblasting damage were tested. The results show that the depth of compressive stress layer of chemically strengthened lithium aluminosilicate glass is significantly greater than that of chemically strengthened aluminosilicate glass. The compressive stress of aluminosilicate glass and lithium aluminosilicate glass after chemical strengthening varies differently along the thickness direction. The compressive stress of aluminosilicate glass is greater than that of lithium aluminosilicate glass within 40 μm depth range, while the compressive stress of lithium aluminosilicate glass is greater than that of aluminosilicate glass when the depth exceeds 40 μm. After sandblasting damage, the residual flexural strength of aluminosilicate glass is greater when the damage depth is within 40 μm depth range, while the residual flexural strength of lithium aluminosilicate glass is greater when the damage depth is further increased to more than 40 μm. Chemically strengthened lithium aluminosilicate glass has a greater advantage in residual flexrual strength after surface damage compared to aluminosilicate glass.

Fe-Mn-Al-Ni based shape memory alloys exhibit an extremely low temperature dependence of the critical stress of martensitic transformation and display great superelastic temperature ranges (-263 to 240 °C). Therefore, these shape memory alloys show promising applications in aerospace, space exploration, vibration damping, and other environments with variable working conditions. In this work, the main factors affecting the superelasticity of Fe-Mn-Al-Ni based shape memory alloys were reviewed and prospected. Since the precipitation of coherent B2 nano-phase plays the key role in the martensitic transformation from non-thermoelastic to thermoelastic in Fe-Mn-Al-Ni-based shape memory alloys. The mechanism by which the coherent B2 nano-phase modulates the martensitic transformation of Fe-Mn-Al-Ni-based shape memory alloys and the related progress of its size regulation were firstly discussed. Since the superelasticity of Fe-Mn-Al-Ni-based shape memory alloys is known to be positively correlated with the grain size, the preparation of single crystals is a prerequisite for achieving excellent superelasticity. Therefore, the single-crystal growth studies of Fe-Mn-Al-Ni-based shape memory alloys in recent years were reviewed. Then, the functional properties of single-crystal Fe-Mn-Al-Ni-based shape memory alloys were summarized. Finally, the future research and development of Fe-Mn-Al-Ni-based shape memory alloys were prospected.