Effects of depth of cut on the redistribution of residual stress and distortion during the milling of thin-walled part

Abstract

The distortion of thin-walled part is significantly affected by the residual stress generated after the material is cut away. During this process, the relations between the redistributed residual stress and the distortion are quite complex; as a result the control of distortion of thin-walled part always is being considered tough issues. In this study, an approach of optimizing the profile and magnitude of residual stress is proposed by analyzing the effects of depth of cut on the redistribution of residual stress. Experiments and simulations are conducted to compare the cutting forces, temperature and residual stress. The results show that, in the roughing, by selection of a subsequent depth exceeding prior depth of maximum compressive residual stress, the material which contains the main machined residual stress can be removed in favor of the subsequent machining. Furthermore, in the finishing, different depths of cut are utilized in different cutting stages, resulting in smaller magnitude of maximum machined residual stress and depth of maximum compressive residual stress. In addition, to verify the approach, an aviation thin-walled part is used as the experimental object. The results demonstrate that the magnitude of distortion and residual stress can be decreased and optimized efficiently by controlling and optimizing the depth of cut in the roughing and finishing.