Mechanical Properties and Formation of Phases in High-Entropy CrFeNiCuCoAl_х Alloys

Abstract

In this study, the CrFeNiCuCoAl_х (where x = 0, 0.5, 1, 2, 3) multicomponent alloys were prepared by vacuum arc melting and their phase composition, microstructure and mechanical properties were examined. According to X-Ray analysis data, phase composition of alloys depending on Al content. It was found that the structure is changed from mixture FCC₁+FCC₂ solid solutions into BCC solid solution with the increase of Al content (at x = 3). Microstructure and chemical composition of dendritic and interdendritic regions were investigated by using scanning electron microscopy. The composition of primary and secondary dendrites includes all elements alloy. Interdendritic region has a high content of Cu due to its high positive enthalpy of mixing in pairs with most elements of the alloy. Microhardness increases from 3.1 to 8.4 GPa with increasing concentration of Al in the system CrFeNiCuCoAl_х.