Effect of a multi-phase structure on the damping response of a novel high entropy alloy

Abstract

In this study, dynamic behavior of a novel multi-phase high entropy alloy (HEA) was investigated. Thermo-mechanical processes containing an 80 % thickness reduction at room temperature rolling followed by annealing at 750 °C and 850 °C were applied to modify the microstructure and the resulting damping properties of the HEA. Annealing at 750 °C introduced the BCC phase, while at 850 °C, the sigma phase was prevalent in the microstructure, leading to over 1 GPa strength with decent ductility in the latter condition. The storage modulus and the internal friction values of the annealed alloys are noticeably improved, indicating that application of suitable heat treatments could enhance both the mechanical response and the damping performance of this HEA.