Effective strengthening and toughening in high entropy-alloy by combining extrusion machining and heat treatment

This study presents an effective strengthening and toughening approach to improve tensile properties of CrMnFeCoNi high entropy-alloy (HEA) by combining extrusion machining and short-time heat treatment. After such process, preliminary structural heterogeneity has been achieved in this alloy, of which the strength is significantly enhanced while good elongation is retained compared to its homogeneous conterparts. Microstructural characterization reveals varying degrees of partial recrystallization with more or less dislocation density for HEAs under different treatment. It is such structural inhomogeneity that imparts this alloy with good strain hardening ability at high flow stress levels.