FEM optimization of tool geometry based on the machined near surface's residual stresses generated in diamond turning

Abstract

In this work, based on the updated Lagrangian formulation and the commercial available software, Marc2001, a coupled thermo-mechanical plane-strain large deformation orthogonal cutting FE model is presented to simulate the diamond turning process and predict the residual stresses on the machined surface of workpiece. In order to consider the interactive influences of cutting edge radius, cutting velocity, rake angle and clearance angle on residual stresses, all simulations are programmed by an orthogonal design method, i.e. the combination design of general rotary method. As expected, two regression equations of tensile and compressive residual stresses are deduced according to the simulated results. The measured results in diamond turning show that the predicted results have a good consistency with the experimental ones. Therefore, some related analyses are carried out for the influencing factors based on the regression equations. Finally, the optimal analyses indicate that a rake angle of 15° and a clearance angle of 10° are the optimum geometry of a diamond tool in turning of ductile materials when this tool has a cutting edge radius of 100–300 nm.