Generation Mechanism of Work Hardened Surface Layer in Metal Cutting. 1st Report. Study on Mechanical Factors in Generation Mechanism of Work Hardened Surface Layer.

Abstract

Finish machining used to be carried out in grinding, but it is being replaced by cutting with very small undeformed chip thickness. In super precision process, the effect of the cutting conditions and complicated factors on the machined surface integrity is a serious problem. In this research, work hardened surface layer was dealt with as an evaluation of machined surface integrity and the effect of the mechanical factors on work hardening was investigated experimentally in orthogonal cutting. As a result, it is better to deal with a shear angle and shear zone separately as a factor affecting a work hardened surface layer. Furthermore, it was found that not only the shear angle with variation of the cutting conditions but also the thickness of plastic deformation zone have effect on the depth of the work hardened surface layer below the machined surface after orthogonal cutting.