退火对CrCuFeMnTi高熵合金组织结构和力学性能的影响

In order to investigate the effect of annealing treatment on microstructures and mechanical properties of CrCuFeMnTi high entropy alloy, a as-cast CrCuFeMnTi alloy ingot was prepared by vacuum arc melting under the argon protection, and then the microstructures observation and mechanical properties testing of alloy samples under annealing treatment at different temperatures were performed. The results show that the as-cast CrCuFeMnTi alloy is composed of a hexagonal close packed phase and a face centered cubic solid solution, and typical microstructures with dendrite and interdendrite phases are observed. There is mainly element diffusion and morphology homogenization when the annealing temperature is under 750℃, and the hexagonal close packed phase will transform into body centered phase after the alloy is annealed at 900℃. Element diffusion causes the phase transition and controls it. The hardness and strength of the alloy are all improved when the alloy is annealed below 750℃; meanwhile, all the fracture exhibits a brittle character.