Effect of room temperature rolling and annealing on microstructure and mechanical properties of (CrCoNi)96V4 medium entropy alloy

As cast (CrCoNi)₉₆V₄ medium entropy alloy（MEA）was prepared by vacuum arc melting. The MEA is deformed by rolling at room temperature with a total deformation of 67 %, The yield strength and tensile strength of the deformed MEA are 1297 MPa and 1410 MPa respectively, the elongation of the alloy is only 8 %.Then the deformed MEA was annealed for 30min at 700 °C, 800 °C and 900 °C respectively. The results show that the strength and ductility of the MEA after annealing were well balanced. The yield strength and tensile strength of the MEA after annealing at 900 °C/30 min are 678 MPa and 1024 MPa, and the elongation is maintained at 26 %. After annealing, a large number of annealing twins were formed in the MEA, which makes the strength and ductility of the MEA significantly improved. At the same time, Cr-rich particles were found in the MEA, which had positive effect on the improvement of the strength and ductility of the alloy.