Microstructure and texture evolution during annealing of equiatomic CoCrFeMnNi high-entropy alloy

Evolution of microstructure and texture after heavy cold rolling and subsequent annealing in a wide temperature range was first studied in an FCC equiatomic CoCrFeMnNi high-entropy alloy (HEA). Development of a submicron-cell structure and a strong brass-type texture was observed after 90% cold rolling. An ultrafine microstructure having average recrystallized grain size similar to 1 mu m with profuse annealing twins was observed after annealing at 650 degrees C. Remarkable resistance against grain coarsening was observed at least up to 800 degrees C. The mechanisms for these features were closely related with the distinct whole-solute matrix in HEAs. The recrystallization texture was characterized by the retention of deformation texture components similar to those of TWIP and 316 stainless steels. But notable differences exist. The S ({123}< 634 >) component is stronger than brass ({110}< 112 >) and Goss ({110}< 001 >), and strengthened with increasing annealing temperatures. Strong alpha-fiber (< 110 >//ND) components other than the deformation components B-S and G, and higher fraction of random components also develop. It could be attributed to profuse annealing twin formation due to the low stacking fault energy of the alloy. (C) 2013 Elsevier B.V. All rights reserved.