Prediction of the Principal Stress Direction for 5-axis Ball End Milling

While regenerating damaged components, e.g. compressor blades, the removal of excess weld material called re-contouring often determines the surface integrity including the residual stress state. A load-specific residual stress state is beneficial for lifetime. This leads to the necessity to predict the resulting residual stress state after machining. The paper describes two models, which predict the principal stress direction as a residual stress characteristic for 5-axis ball nose end milling of Ti-6Al-4V. One model uses process force components, the other is based on the microtopography of the workpiece, which is influenced by the kinematics of the process.