A thermo-mechanical coupled model of derivative cutting of microtextured tools

Abstract

In our previous works, the revelation of the significance of derivative cutting in the cutting process with microtextured tools, which occurs because of the finite sharpness of the texture edge at the tool-chip interface, serves as a starting point for exploring of the cutting mechanism. At present, a thermo-mechanical coupled model for orthogonal cutting process is formulated to predict cutting force under effect of derivative cutting in terms of the structural and positional parameters of textures, cutting conditions, and material properties. The flow stress model considering size effect is combined with the Oxley’s cutting model to predict derivative chip formation force. Meanwhile, the Waldorf’s slip-line model is applied to evaluate plowing force in derivative cutting. The cutting temperature is predicted based on the heat source theory, which is integrated with the proposed model of derivative cutting to build up the coupled iterative model. A series of orthogonal cutting tests are carried out to validate the prediction model by using different types of microtextured tools. The measured values of cutting force show a good agreement with the predictions. Furthermore, the proposed method provides some insights into ways to diminish the adverse effect of derivative cutting. Results show that the reductions in the edge radius and the inclined angle of textures contribute to decreasing derivative cutting force with increasing cutting velocity.