Assessment of deformation of a shear localized chip in high speed machining

As the cutting speed increases, the mechanism of chip deformation will be changed significantly, i.e., a continuous chip at low cutting speed will shift to a serrated chip with shear localization. For the shear localized chip, the parameters used to assess the chip deformation for a continuous chip, such as shorten coefficient ξ, shear angle φ and shear strain ε, cannot describe the chip deformation correctly or comprehensively. This paper deals with the assessment of the chip deformation of shear localization and advances equations to calculate the shear strains of the shear band and chip segment and shear rate. By the use of this assessment, the chip deformation in machining selenium-treated stainless steel (STSS) and common stainless steel under various cutting conditions is investigated.