Effect of cold-rolling strain on the evolution of annealing texture of equiatomic CoCrFeMnNi high entropy alloy

The effect of cold-rolling strain on the evolution of microstructure and texture during annealing was studied in an equiatomic CoCrFeMnNi high entropy alloy. For this purpose the alloy was cold-rolled to 60%, 80% and 95% reduction in thickness. The three cold-rolled materials were isochronally annealed for 1 hat temperatures ranging between 700 degrees C and 1200 degrees C. With increasing rolling reduction, the texture transition from pure metal type (<60% reduction) to an alloy type texture (>80% reduction) was observed. The final recrystallized grain size was found to decrease systematically with increasing prior cold-rolling strain. However, the effect was much less pronounced below the annealing temperature of 1200 degrees C due to sluggish diffusion in the HEA. The recrystallization texture of different deformed materials showed the presence of similar texture components indicating that prior deformation had only limited effect on the formation of annealing texture. The typical annealing texture components of low SFE materials, such as {236}< 385 > or {113}< 332 > were not the dominant components. The volume fractions of different texture components also did not reveal significant dependence on the annealing temperature. The evolution of annealing texture in the HEA could be adequately explained by the absence of strong preferential nucleation and growth. (C) 2015 Elsevier Inc. All rights reserved.