Enhanced phase stability of a BCC structure system high-entropy alloys by decreasing elastic distortion energy

Abstract

Lightweight BCC high-entropy alloys exhibit outstanding specific strength. However, these alloys usually have poor phase stability, causing brittle precipitates. These precipitates would worsen the plasticity. In order to improve the alloy performance, it is important to improve its phase stability. In this paper, the phase stability of two kinds of BCC high-entropy alloys at 400°C, 500°C and 600°C is investigated. The contributions of mixing enthalpy and elastic distortion energy to their phase stability are discussed. Besides mixing enthalpy, elastic distortion energy also plays a significant role in phase stability. Our results prove that decreasing elastic distortion energy is an effective way to improve phase stability of typical BCC HEAs.