Kinetics of recrystallization and grain growth in an ultra-fine grained CoCrFeNiMn-type high-entropy alloy

M V Klimova,D G Shaysultanov,R S Chernichenko,N D Stepanov,V N Sanin,S V Zherebtsov

doi:10.1088/1742-6596/1270/1/012053

Abstract

A novel high entropy alloy based on the CoCrFeMnNi system with substantial amounts of Al and C was studied. After cold rolling and annealing at 973-1273 K a duplex ultra-fine grained structure composed of the recrystallized fcc grains and M23C6 and B2 particles was produced. Analysis of the coarsening behavior of grains and particles growth suggested that kinetics of both was controlled by volume diffusion. The apparent activation energy of structure coarsening during recrystallization was evaluated.

Highlights

The so-called high entropy alloys (HEAs), multicomponent alloys of 5 or more principal elements taken in nearly equiatomic concentration (5-35 at.%), have become a very attractive research field in materials science [1,2]
Cold rolling and annealing in the interval of 973-1273 K resulted in the formation of a duplex ultrafinegrained structure composed of the recrystallized fcc grains and M23C6 type carbides and B2 particles
A further increase in the annealing temperature or time resulted in a remarkable decrease in the hardness in all interval of annealing times which associated with primary static recrystallization

Summary

Introduction

The so-called high entropy alloys (HEAs), multicomponent alloys of 5 or more principal elements taken in nearly equiatomic concentration (5-35 at.%), have become a very attractive research field in materials science [1,2]. A typical and well-investigated representative of this family is the equiatomic CoCrFeMnNi alloy, known as the Cantor alloy [4,5,6,7]. This alloy has a single disordered face-centered cubic (fcc) structure at temperatures >900°C [6,8,9,10,11,12,13] and is widely considered as a “model” single phase HEA. The alloy has attractive mechanical properties; namely very high ductility and fracture toughness at room temperature [5,7], which yet increases even more under cryogenic condition. The strength of the alloy is quite low [5,11]

Methods

Results

Conclusion