Finite Element Modeling of Hard Turning

Due to its favorable effects on the machined surface, hard turning processes are replacing grinding for finishing various mechanical components of hardened steels such as transmission shafts, bearings and gears. During hard turning, the cutting tool is exposed to a very severe environment. The specific cutting stresses and the temperatures are high. For a tool to perform successfully under these severe conditions and to have a good surface quality, factors such as the cutting tool edge geometry, feed rate, and cutting speed have to be carefully selected. In this study, the finite element method (FEM) is used as a tool for understanding the fundamentals of hard turning process and for the prediction of the effect of CBN tool edge preparation and cutting conditions on the process variables. In addition, a methodology for obtaining flow stress data for machining simulations from machining and compression tests has been developed. Since practical hard turning is a 3D process, two numerical methods are used to study te process: 1) simplification of the 3D hard turning process using an analytical model and 2D FEM and 2) 3D FEM.