Low temperature processing and annealing effects on slip band formation, annealing twins and grain boundary segregation in a high entropy alloy

Abstract

High entropy alloys have the potential to be processed at low temperatures and can be used at relatively high temperatures. However, there are some concerns regarding segregation of constituent elements and homogenization. In this regard, the study focuses on studying the significance of combining cryo-rolling and annealing in the context of grain boundary segregation. Furthermore, the study also focuses on the impact of cryo-rolling on the formation of micro-scale defect structures and evolution of recrystallized structure on annealing. Cryo-rolling induced a high density of slip bands and consequently high stored energy, which accelerated the kinetics of recrystallization, together with the formation of annealing twins of different morphology. The high degree of strain (defect structures) provided diffusion paths for atoms during annealing such that the micro-scale grain boundary segregation was not observed.