Simultaneously increasing the strength and ductility of a refractory high-entropy alloy via grain refining

The HfNbTaTiZr refractory high-entropy alloy was investigated on the grain growth kinetics and tensile properties. Grain growth at 1200-1350 degrees C is rather slow. The activation energy is 389 kJ/mol and the growth exponent is 3.5. The HfNbTaTiZr alloy has high strength, small work hardening and high ductility. Grain refining is found to enhance the tensile strength and ductility simultaneously. (C) 2016 Elsevier B.V. All rights reserved.