A numerical study on nanometric cutting mechanism of lutetium oxide single crystal

It is hard for ultra-precision machining to realize nanometric accuracy on lutetium oxide single crystal. However, molecular dynamics analysis can be employed to reveal the atomic scale details of material removal process, providing a theoretic basis. This article focuses on both cutting speed and cutting depth, analyzing the influence on cutting force, stress distribution, subsurface deformation and crack formation. The results show that amorphization takes place in the region which undergoes a high compressive stress. Crack initiation emerges with a release of tensile stress and is always accompanied with a sharp drop in cutting force. A higher cutting speed and larger cutting depth result in a larger critical local tensile stress for crack initiation. Cutting zone and interface area are prone to damage concentration. Once these damages combine together, there would be a visible bulk material peeling off.