On Stress Analysis of Diamond Coating Cutting Tools

Diamond coatings have been increasingly used in cutting tools applications. Coating delamination is the major tool failure mode and occurs due to deposition-induced residual stresses and thermomechanical loading in machining. This study applies finite element analysis to investigate stress distributions, with the edge radius focused, in diamond coating tools considering depositions and machining. After depositions, the residual stresses around the edge are compressive and tensile for the radial and tangential components, respectively, with high stress concentrations. The stress concentrations can be alleviated by a large edge radius. When machining loading is imposed, stress reversal occurs on both components, i.e., radial (or tangential) stresses shifting toward less tensile (or compressive). For the edge radius effects, at a low feed, increasing the hone radius will reduce the maximum tangential normal stress (from compression toward tension). However, the edge radius seems to have minor effects at a high feed.