Solute segregation effect on grain boundary migration and Hall–Petch relationship in CrMnFeCoNi high-entropy alloy

Abstract

Homogenisation has been used to eliminate solute segregation of CrMnFeCoNi high-entropy alloys (HEAs) before thermomechanical processing. To overcome the deficiencies caused by high-temperature homogenisation, we cancelled the homogenisation and studied the solute segregation feature and its effect on the grain growth and the mechanical property. The HEA forms equiaxed grains with the solute segregation in the range of tens of micrometres after cold rolling and recrystallisation. The grain growth in recrystallisation still abides by the classical grain growth kinetics, but with a higher power index of 3.33 and activation energy of 392.4 kJ mol⁻¹ than those of the homogenised HEA, indicating a solute-drag effect. The relationship between the yield stress and grain size follows the Hall–Petch dependence with a higher intrinsic strength.