Microstructure, mechanical and tribological properties of CoCrFeNiMn high entropy alloy matrix composites with addition of Cr3C2

Abstract

CoCrFeNiMn high-entropy alloy (HEA) matrix composites with different mass fraction of Cr3C2 are produced by spark plasma sintering. The composites are composed of HEA's face-centered-cubic and Cr7C3 phases. When addition of Cr3C2 increases, the hardness and yield strength of composites increase. The friction coefficients at room temperature (RT), 200 and 800 °C exhibit a decreasing tendency with the increase of Cr3C2 content. The wear rates decrease from RT to 800 °C when adding 10% Cr3C2 in CoCrFeNiMn HEA. The wear mechanisms of CoCrFeNiMn HEA matrix composites are governed by abrasion and adhesive wear from RT to 400 °C, and change to oxidation wear above 400 °C. Combined the mechanical and tribological properties, CoCrFeNiMn-10% Cr3C2 composite possesses the best comprehensive properties.