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High-entropy alloys have attracted great attention in various fields due to their high-entropy effect, severe lattice distortion, slow diffusion and special and excellent material performance due to the combination of various alloying elements in equal or near-equal molar proportions. Its high strength and hardness, fatigue resistance, excellent corrosion resistance, radiation resistance, near-zero thermal expansion coefficient, catalytic response, thermoelectric response and photoelectric conversion make high-entropy alloys have potential applications in many aspects. High-throughput computation and machine learning technology have rapidly become powerful tools to explore the huge composition space of high-entropy alloys and comprehensively predict material properties. The basic concepts of high-throughput computing and machine learning were introduced in this paper as well as the advantages of first-principles calculation, thermodynamic/kinetic calculation and machine learning in the research of high-entropy alloys. The application research status of high-entropy alloy composition screening, phase and microstructure calculations and performance prediction were summarized. In the final part, the existing problems, and the solutions and future prospects of this field were summarized, including developing tools for first-principles calculations and machine learning of high-entropy alloys, building high-quality databases for high-entropy alloys and integrating high-throughput computing with machine learning to globally optimize the mechanical property and service performance of high-entropy alloys.

The mechanical properties of high‐speed steel (HSS) are significantly influenced by the distribution of carbides formed during solidification. Despite extensive research, the nonuniform cooling in large ingots remains an area requiring further investigation. In this study, the microstructure inhomogeneity in M42 HSS with a diameter of 330 mm is examined. Models are developed to predict the dissolution of carbide networks during homogenization, achieving a 39% reduction in hardness variation (Δr) between the center and surface. Further improvements are attained through hot forging and rolling, leading to the fragmentation of the carbide network into a banded structure. Additionally, a detailed carbide tip dissolution model is established, providing a reliable basis for optimizing annealing processes. As a result, the carbide distribution converges significantly, with hardness variations reduced by 88% to only 0.3 hardness Rockwell C scale, showcasing substantial enhancement in material homogeneity. [ABSTRACT FROM AUTHOR]

We studied a gradient anti-oxidation coating of C/C composite materials for aircraft brake discs with a simple process and low costs. The gradient coating consists of two layers, of which the inner layer is prepared with tetraethyl orthosilicate (Si (OC2H5)4), C2H5OH, H3PO4 and B4C, and the outer layer is prepared with Na2B4O7.10H2O, B2O3, and SiO2 powder. The experimental results show that after being oxidized at 700 °C for 15 h, the oxidation weight loss of the sample with the coating was only −0.17%. At the same time, after 50 thermal cycles in air at 900 °C, the sample's oxidation weight loss was only −0.06%. We conducted the 1:1 dynamic simulation test for aircraft brake discs, and the brake disc did not oxidize, thus meeting the requirements for aircraft use. In addition, the anti-oxidation mechanism of the coating was analyzed via scanning electron microscopy (SEM), X-ray diffraction (XRD), differential thermal analysis (DSC-TGA), and high-temperature in situ SEM. [ABSTRACT FROM AUTHOR]

MoCoB‐based cermets have been regarded as the potential substitution of WC cermets with high hardness, high melting point and high oxidation resistance. Ternary borides‐based cermets are widely used in extreme environment, such as high‐pressure environment. Therefore, it is significant to explore the mechanical properties and electronic structures of transition elements X (X = V, Mn, Fe, Ni) atoms doped MoCoB under high pressure, which are performed by first‐principles calculations to provide guidance for industry applications. The analysis of cohesive energy and formation enthalpy indicates high pressure leads to unstable states with lower lattice constants and crystal volumes. The deviation of cohesive energy and formation enthalpy indicate Mo4Co3FeB4 and Mo4Co3NiB4 have similar stability. The shear modulus, Young's modulus and bulk modulus increase under high pressure, which consists with the increasing of covalence. The variation of ductility and anisotropy indicate similar upward trend, which is verified by Poisson's ratio, B/G ratio and anisotropy index AU. The analysis of overlap population indicates high pressure leads to the increasing of covalence of B‐Co covalent bonds and the decreasing of the covalence of B‐Mo covalent bonds. The analysis of electronic structures indicates the high pressure leads to higher hybridization and lower density of states of metallic bonds. The analysis of charge density difference consists with the variation of mechanical properties, implying shorter bond length and higher bonds strength under high pressure. [ABSTRACT FROM AUTHOR]