Enhanced prediction of residual stress in milling through considering cutter runout

Cutter runout occurring in milling usually leads to uneven cutting forces, which thus affect the distribution of residual stress. However, its influence on milling residual stress is rarely reported in existing literature. Hence, this article presents a novel model to predict milling residual stress through including the effect of cutter runout. The model incorporates the influence of cutter runout in predicting cutting forces, which are subsequently utilized to individually predict mechanical and thermal stresses induced by each cutting edge. With the aid of elastoplastic theory, the loading and unloading procedures are established to model the distributions of stress and residual stress stemming from two consecutive tooth periods, constructing the theoretical model of milling residual stress involving the effect of cutter runout. Predicted results show that cutter runout induces uneven residual stresses across two consecutive tooth periods, thus leading to varying residual stress distributions within the workpiece. A series of milling tests demonstrate a close agreement between the predicted and measured residual stresses. Especially, both finite element simulations and experimental measurements confirm that residual stress induced by cutter runout can result in obvious deformations of thin-walled workpieces in milling processes.