Nanocutting mechanisms of Cu50Zr50 amorphous alloy: A molecular dynamics simulation

Amorphous structures can achieve high mechanical strength and toughness, excellent magnetic properties, anti-corrosion, and anti-friction properties, resulting in their wide applicability, thereby prompting research interest in the role of nanofabrication for amorphous alloys. In this study, the deformation behavior of amorphous alloy Cu50Zr50 during nano cutting was investigated via molecular dynamics simulations. By analyzing the variations of the displacement vector, shear strain, cutting force, and cutting temperature, the removal mechanism of the amorphous alloy material was studied in detail. The amorphous alloy was removed via extrusion during nano cutting. The shear transition zone was formed via the local atomic superposition to form a shear band, and the atoms recovered elastically to form a machined surface. The effects of the cutting depth, cutting speed, and tool angle on the deformation behavior of the material were investigated. The results indicate that the cutting force, cutting temperature, and friction coefficient are increased with an increasing in cutting depth. An appropriate increase in the clearance angle and decrease in the rake angle can reduce the cutting force and friction coefficient. Based on the evolution law of the surface, the plastic transformation of the cutting amorphous alloys was predicted. At the cutting speed of 100–200 m/s, the friction coefficient remained unchanged, which accelerated the formation of a plastic transition zone. For different machining angles, the largest cutting force and surface roughness were obtained at 45°, whereas the least values were obtained at 60°. Therefore, the different machining angle can reduce the cutting forces and improve the quality of the machined surface.