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This study investigates how thermal conditions affect the nanomachining of FeCoNiCrAl high-entropy alloys, using molecular dynamics simulations at 100K, 150K and 200K. Key findings include a direct relationship between stress intensification and machining velocity at all temperatures, with stress concentrating at intergranular boundaries. At subsonic speeds ($<$200m/s), stress inversely correlates with temperature, while at supersonic speeds ($>$200m/s), stress increases with temperature. Incremental cutting depths affect chip morphology, with chips at 150K being 1.38 times thicker than at 200K. Minimum machining forces were 94.5Nn, 101.2Nn and 92.5Nn along [100], and 87.3Nn, 85.3Nn and 86.1Nn along [001]. Dislocation densities showed higher values at lower temperatures, with peak 1/2 $〈110〉$ densities at 100K being 1.43 and 1.45 times greater than at 150K and 200K, respectively.

A high entropy alloy of composition CoCrCuFeNiAl_0.5 is mainly composed of a face centered cubic (FCC) solid solution phase. The tensile and compressive properties of the alloy were investigated; the alloy exhibited a tensile strength of 707 MPa, together with a large plastic strain limit of 19%.

In this study, the effects of Al${}_x$CoCrFeNiCu high entropy alloy (HEA) binder on the phase composition, microstructure, hardness, fracture toughness and abrasion resistance of Ti(C, N) cermets prepared by powder metallurgy method were investigated by X-ray diffraction, scanning electron microscopy, mechanical properties and abrasion test. The results showed that the sintered Ti(C, N) cermets exhibit homogeneous core-shell microstructure at 1500${}^{\circ }$C when HEAs with 0.2 at% aluminum were added. The Vickers hardness and fracture toughness of cermet with Al${}_{0.2}$CoCrFeNiCu could reach the peak value of 2235 Kg/mm² and 10.51 MPa$\ast$m${}^{1/2}$ and the fracture morphology showed mixture fracture. The Ti(C, N) cermets with HEA binder exhibited good friction and wear properties.

High-entropy alloys (HEAs) have shown considerable promise from both a scientific and an application perspective due to their outstanding comprehensive properties. In this study, an equiatomic FeCoCrNi HEA is used as input material for laser cladding on Ti-6Al-4V alloy. The HEA coating is characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) to investigate the bonding region, element distribution and microstructure evolution. The results show that the HEA coating is mainly composed of face-centered cubic (FCC) phase and body-centered cubic (BCC) phase, precipitating a small amount of (Fe, Cr)-rich phase and (Ni, Ti)-rich phase. Otherwise, the bonding region, which is between coating and substrate, is emphatically concerned in this paper. The bonding region is formed by the convection zone which is resulted from the density difference of HEA and TC4. In addition, the convection in molten pool plays a key role in the morphology of bonding region.

The CrCuFeMnNi high entropy alloy (HEA) powder was synthesized by mechanical alloying. The effects of milling time and subsequent annealing on the structure evolution, thermostability and magnetic property were investigated. After 50h of milling, the CrCuFeMnNi HEA powder consisted of a major FCC phase and a small amount of BCC phase. The crystallite size and strain lattice of 50h-ball-milled CrCuFeMnNi HEA powder were 12nm and 1.02%, respectively. The powder exhibited refined morphology and excellent chemical homogeneity. The supersaturated solid solution structure of the as-milled HEA powder transformed into FCC1, FCC2, a small amount of BCC and $\rho$ phase in annealed state. Most of the BCC phase decomposed into FCC (mainly FCC2 phase) and $\rho$ phases, and the dynamic phase transition was almost in equilibrium at 900${}^{\circ }$C. The saturated magnetization and coercivity force of the 50h-ball-milled CrCuFeMnNi HEA powder were respectively 16.1emu/g and 56.2Oe.

The superconductivity in the actinide-based high entropy alloy superconductor (AHEASC) (TaNb)_x(TiUHf)${}_{1-x}$ is studied in the framework of Bardeen–Cooper–Schrieffer (BCS) theory, and McMillan’s formalism has been studied for the investigation of superconducting state (SC) parameters, viz., Coulomb pseudopotential ${\mu }^{\ast }$, electron–phonon coupling strength $\lambda$, SC transition temperature $T_C$, interaction strength $N_{0}V$, band gap $\mathrm{\Delta }$, energy or mass renormalization parameter $Z_0$, and isotope effect exponent $\delta$. BCS theory in conjunction with McMillan’s formalism has been used for the investigation. The study indicates a strong correlation between the electron–phonon interaction, and the superconducting properties of the high entropy alloy (TaNb)_x(TiUHf)${}_{1-x}$ are highly dependent on its composition. An abrupt change in the isotope effect exponent suggests the presence of additional mechanisms such as magnetic interactions, spin fluctuations, or strong electron correlations.

This paper employs a first-principle approach to systematically investigate the superconducting state parameters in (TaNb)_X(TiZrHf)${}_{1-X}$ alloys (where X varies from 0 to 1). Utilizing advanced computational techniques, we elucidate the critical factors influencing the superconducting behavior of this mixed-metal system. Our study provides valuable insights into the tuning of critical temperature ($T_C$) and other essential parameters, offering a comprehensive understanding of the superconducting properties. It has been that, due to the simple averaging effect of the individual density of states (DOS) contributions and consistent increase in the electrostatic repulsion between ions, the DOS and Coulomb pseudopotential increase linearly with concentration. The lattice disorder and weak isotope effect affect the electron–phonon coupling strength thereby affecting the critical temperature ($T_C$) of the material. The outcomes contribute to the design and optimization of novel superconductors with potential applications.