Prediction of the critical cutting conditions of serrated chip in high speed machining based on linear stability analysis

Abstract

A new prediction model was proposed to give the critical cutting condition of serrated chip in high speed machining, including cutting speed, depth of cut, and rake angle. Firstly, a critical criterion of serrated chip in high speed machining was obtained through the linear stability analysis of balance equations of continuum mechanics for primary deformation zone, which considers the influence of compression stress through stress equivalent. Secondly, the model of deformation in the primary deformation zone was proposed to build the corresponding relationships between the cutting conditions and the deformation conditions based on the model of parallel boundary shear zone. Lastly, the critical cutting condition of serrated chip in high speed machining can be predicted by combining the critical criterion and the calculation of deformation conditions in the primary deformation zone. For the validation of model, the critical cutting conditions of serrated chip on AISI 1045 steel were predicted and an orthogonal cutting experiment was performed for comparing with the prediction results. The comparison shows that the prediction results agree well with that of experiment. Therefore, the proposed model is available. This is very useful for the optimization of cutting parameters and precision control of high speed machining.