An Analysis of Cutting Parameters, Coated Materials and Nose Radii on Residual Stresses When Turning Inconel 718

As a critical characteristic parameter of surface integrity, residual stresses on the machined surface and the subsurface have a huge influence on the service quality of a component, such as fatigue life. In this paper, a comprehensive study about the effects of coated materials, nose radii and cutting parameters on finish turning processes is presented. The results show that turning by PVD coated tool with smaller nose radius can produce higher compressive residual stresses or lower tensile residual stresses which can extend the fatigue life of parts. A finite element model is established to explain the difference in residual stresses, it shows that the thermal loads play a dominant role in the generation of residual stresses.