Effect of Cutting Parameters on Nano-Cutting of Single Crystal γ-TiAl Alloy with Water Medium via Atomistic Simulation

Abstract

In this paper, molecular dynamics (MD) simulations are used to investigate the effects of machining parameters on the nanomachining and subsurface defect evolution of single crystal γ-TiAl alloys with water medium. The changes of cutting force and cutting temperature with water medium were analyzed in the nano-cutting process, and the subsurface defects and crystal structure changes of the workpiece were studied by common neighbor analysis (CNA) method. The results show that increasing the cutting speed appropriately can reduce the friction between the workpiece and the tool, and improve the machining efficiency. With the increase in cutting depth, the temperature of the Newtonian layer increases gradually, and the cooling of the water medium reduces the temperature of the workpiece. The defect evolution becomes severe and the number of BCC atoms increases with the increase in cutting depth. With the increase in cutting distance, the number of HCP atoms decreases and the number of BCC atoms basically remains stable. In addition, as the cutting speed increases, the internal stress of the workpiece gradually extends to the inside of the workpiece along the depth direction. There is more compressive stress in the unmachined area and the shear zone between the tool and the workpiece.