Formation and Anisotropic Mechanical Behavior of Stacking Fault Tetrahedron in Ni and CoCrFeNiMn High-Entropy Alloy

Stacking fault tetrahedron (SFT) is a kind of detrimental three-dimensional defect in conventional face-centered cubic (FCC) structural metals; however, its formation and anisotropic mechanical behavior CoCrFeNiMn high-entropy alloy (HEA) remain unclear. In this work, we first performed molecular dynamics simulations to verify the applicability Silcox-Hirsch mechanism HEA. The responses SFT shear stress different directions that pure Ni counterpart were simulated, evolutions atomic structures SFTs during analyzed detail. Our results revealed evolution has patterns, including annihilation stacking faults, expansion new insignificant changes faults. It was found effects on elastic properties HEA are negligible. However, introduction would reduce critical stress, while much less sensitive than Ni.