Tensile properties of AlCrCoFeCuNi glassy alloys: A molecular dynamics simulation study

High-entropy alloys (HEAs) are among multi-component alloys with attractive microstructures and mechanical properties. In this study, molecular dynamics simulation was used to determine the tensile behaviour of glassy AlxCrCoFeCuNi HEAs from 300°K to 1300°K. For this purpose, this alloy with variations in chemical concentration of aluminum were heated and then cooled at a high cooling rate of 21.1×1012K/s. Results from radial distribution functions (RDF) and common neighbor analysis (CNA) indicated that no crystalline structures were formed for these glassy alloys. The deformation behaviour and mechanisms of the glassy alloys at room and high temperatures and various strain rates were investigated and reported. The tensile test results showed that the yield stress decreased markedly as temperature was increased for all the alloys. The alloys exhibited superplastic behaviour for all test conditions. More importantly, by increasing the molar ratio of aluminum from 0.5 to 3.0, the yield stress and elastic modulus decreased considerably. Also, the yield stress increased with increasing the strain rate for all samples with different aluminum concentrations. Free volume content of the alloys as well as shear banding were evaluated for these alloys to aid explanation of these results.