Deformation behaviour and microstructural evolution of high-entropy CoFeMnNi alloy at hot deformation condition with low strain rate

Abstract. High-entropy alloy is a promising structural material for high-temperature service applications due to the designable superior properties. Superplasticity, normally achieved at relatively high temperature and low strain rate, enables difficult formation materials manufacture complex-shaped parts. This paper presents feasibility experimental study on deformation microstructure of CoFeMnNi high-entropy under hot conditions with rate. A series uniaxial tests were conducted range between 800-1000℃ typical rates 10-4 10-5/s determine stress-strain behaviours. Additionally, understand mechanism, evolution after was characterized. Finally, mechanism based constitutive model developed, which facilities process optimization by finite element simulations.