Material characterization in the chip-tool deformation zone: An application of boundary-layer theory

In high speed metal cutting the shear strain in the secondary shear zone is confined to a plastic boundary layer which is similar to that fluid mechanics. The material behavior in this zone can be described in terms of rheology as a Bingham plastic flow. In the present paper Oldroyd's solution for the plastic boundary layer near a semi-infinite thin knife is applied to the secondary shear zone. Results for boundary-layer thickness, shear strain rate and shear flow strength are obtained and compared with experimental data. The comparisons are encouraging.