Mechanism of void interaction and closure in nanocutting of amorphous alloy

In this study, the effects of voids on the deformation behavior and the removal mechanism of amorphous alloys with continuous void structure were revealed by analyzing atomic displacement, cutting forces, and shear strain. The results indicated that shear and extrusion were the main removal mechanisms for amorphous alloys with continuous void structure. The presence of void structures led to a reduction in both the tangential and normal forces and a bigger effect on the normal force than on the tangential force. However, an increase in void diameter causes a decrease in temperature and cutting forces and a reduction formation rate of plastic deformation regions. In addition, it was founded the machining forces and friction coefficients were strongly influenced by the void size comparing with no void workpieces. As the pore size increases, there is a gradual decrease in the friction coefficient. Furthermore, a novel model considering the interaction between the tool and voids was developed to analyze the mechanism of void closure. The model indicated that a faster voids closure and a larger plastic deformation region were observed with an increase of the depth of cut. As the cutting distance increased, the voids were closed due to the machining induced hydrostatic stress. The closure of continuous voids occurred in a similar way without a critical value for the distance and size between voids. Based on the traditional cutting theory, a void processing efficiency formula was established to study the effect of void structure and cutting speeds on the processing efficiency.