Effect of Re, temperature and σ phase on mechanical behaviors of W-Re alloys: A molecular dynamics study

Tungsten-rhenium (W-Re) alloys are important in high-tech fields such as aerospace and nuclear industries. However, quantitative studies on their underlying mechanisms are rarely reported. Previous molecular dynamics simulations have been based on defect-free W-Re alloy models, which contradict the real scenarios involving initial defects (such as dislocation loops). This study employs molecular dynamics simulations to investigate the effects of different rhenium (Re) contents, temperatures, and σ phase sizes on the tensile mechanical behavior and microscopic deformation mechanisms of W-Re alloys with initial dislocation loops. The results show that the presence of Re induces a decrease in the Young's modulus and yield stress. Re atoms impede dislocation slip and promote dislocation reactions. An increase in temperature significantly reduces the elastic modulus and tensile strength. The presence of dislocation loops and σ phase both leads to alloy embrittlement, with the embrittlement effect becoming more pronounced as the size of the σ phase increases.