Tensile properties and molecular dynamics simulation of FeCrMnAlxCu high-entropy alloys

Abstract

High-entropy alloys with the composition FeCrMnAl_xCu (where x = 0, 0.1, 0.25, 0.5, 0.75, and 1.0) were synthesized utilizing vacuum arc melting techniques followed by Cu mold casting. This study systematically investigated the effects of different Al contents on the microstructure and mechanical properties of these alloys. The microstructural development and characteristics of FeCrMnAl_xCu high-entropy alloys under uniaxial tensile conditions were examined through molecular dynamics simulations. The experimental results indicated that as the Al content increased from 0 to 1.0, the alloy phase structure of the alloy before and after stretching was composed of FCC and BCC phases. Notably, the proportion of the BCC phase increased after stretching, while the dendrite region expanded and the interdendrite region decreased. The tensile strength decreased by 70.44 %, and elongation decreased by 87.14 % as the Al content increased from 0 to 1.0.t Additionally, molecular dynamics simulations revealed that the phase structure changed from the original FCC to a predominantly BCC configuration with increasing Al content. This increase adversely affected the mechanical properties of the FeCrMnAl_xCu high-entropy alloy, thereby leading to a reduction in dislocation density.