Nonlinear vibration analysis in high speed milling of single crystal silicon considering dynamic cutting thickness

In the milling process, the spindle vibration response is an important factor affecting the machining quality and accuracy. In this article, the mechanism of cutting vibration coupling is analyzed, and the dynamic cutting thickness during the milling process is calculated to make the model more accurate and closer to the actual situation. The five degrees of freedom nonlinear vibration model is established to analyze the instantaneous dynamic behaviour under cutting force and unbalanced mass excitation. The linear stiffness and bearing contact force models of the spindle system are derived by Hertz's contact theory. On the basis of the established simulation model, the effects of unbalanced mass eccentricity, spindle speed, axial preload, milling condition parameters on the dynamic behavior are analyzed. The feasibility of the coupled dynamic model is confirmed through experiments. The motion behaviour of the spindle exhibits rich and complex non-linear phenomena due to the interaction of cutting force and vibration response. Therefore, the proposed model provides a theoretical basis for the prediction of cutting force and dynamic characterisatic during the milling process.