Analysis of tool wear and morphology and residual stress of machined surface in hard turning

Abstract

The precision machining technology of hard turning has always been concerned by scientific research institutions and manufacturing industries. Based on the single factor experiment, the wear of CBN tool, morphology of machined surface, residual stress during hard turning of W6Mo5Cr4V2 are analyzed by scanning electron microscope, ultra depth of field microscope, laser confocal electron microscope and X-ray residual stress instrument. The research results indicate that: (1) Adhesion, oxidation and friction in hard turning are the main causes of tool wear, the most significant turning parameter that affects the wear of CBN tool is turning speed. (2) High machining velocity, small feed and small cutting depth can obtain good machined surface quality. (3) The axial and tangential residual stresses produced by hard turning are mainly compressive stresses. When the turning depth is approximately 0.19mm, the tangential residual compressive stress is transformed into tensile stress.