Analytical modeling of residual stress in orthogonal cutting considering tool edge radius effect

Machining-induced residual stress is a leading cause of machining distortion. Many previous studies have been performed to model the relationship between various impact factors and machined residual stress, such as cutting parameters, lubrication, and cooling conditions etc. While few analytic studies examining the size effect of tool edge radius on residual stress have been performed. In order to better understanding the size effect of tool edge radius on machining-induced residual stress, thermomechanical coupling loading and unloading operations are applied to obtain the machining-induced residual stress on the basis of modeling mechanical loads and thermal loads for cutting with edge radiused cutters. Verification experimental results indicate that the proposed model is effective in judging and analyzing the characteristics of the residual stress profile beneath the machined surface in consideration of the tool edge radius effect. By case studies of Ti-6Al-4V turning those based on the proposed model, it was found that the value of surface residual stress increased with the tool edge radius changed from 0.01 mm to 0.03 mm, and the increased percentage of stresses in cutting and cutting width directions could be 132.6% and 191.1%, respectively. While the peak value of the compressive stress and the depth of the peak value decreased gradually, and the decreased percentages of the peak value of the compressive stress in cutting and cutting width directions are 77.8% and 88.6%. The decreased percentages of the depth of the peak value in cutting and cutting width directions are 47.6% and 63.5%.