Effect of repetitive nano-cutting tool parameters on surface quality and subsurface damage of γ-TiAl alloy

In this paper, the molecular dynamics simulation of the repeated nanocutting of single crystal γ-Tial alloy was carried out by selecting different geometric parameters of the second cutting tool by single factor experiment. The cutting force, friction coefficient, subsurface defects, dislocation evolution and surface roughness of the second cutting were analyzed systematically. The results show that when the tool rake angle is 15°, the surface roughness is lower and the surface quality is better. The influence of different second cutting tool rake angle on the surface roughness is not strong. When the rake angle of the second cutting tool and the radius of edge are constant, the average normal cutting force decreases with the increase of the clearance angle of the tool. Under the machining parameters in this paper, the critical clearance angle of the second cutting of single crystal γ-TiAl alloy is between 10° and 15°. When the tool clearance angle is greater than the critical clearance angle, the average cutting force and the machined-surface roughness no longer change significantly. With the increase of the radius of the second cutting tool, the chip decreases, the subsurface defect increases, and the surface roughness of the machined surface also increases with strong regularity.