摘要
The critical characteristics of adiabatic shearfracture （ASF） that induce the formation of isolated seg-ment chip in high-speed machining was further investi-gated. Based on the saturation limit theory, combining withthe stress and deformation conditions and the modifiedJohnson-Cook constitutive relation, the theoretical predic-tion model of ASF was established. The predicted criticalcutting speeds of ASF in high-speed machining ofa hardened carbon steel and a stainless steel were verifiedthrough the chip morphology observations at various neg-ative rake angles and feeds. The influences of the cuttingparameters and thermal-mechanical variables on theoccurrence of ASF were discussed. It was concluded thatthe critical cutting speed of ASF in the hardened carbonsteel was higher than that in the stainless steel under alarger feed and a lower negative rake angle. The proposedprediction model of ASF could predict reasonable results ina wide cutting speed range, facilitating the engineeringapplications in high-speed cutting operations.
