A reliable method for predicting serrated chip formation in high-speed cutting: analysis and experimental verification

Serrated chip formation influences almost every aspect of a high-speed cutting (HSC) process. This paper aims to develop a reliable method to accurately predict such chip formation processes. To this end, a systematic finite element analysis was carried out and a series of HSC experiments were conducted on a heat treated AISI 1045 steel. It was found that the integrative use of the Johnson-Cook thermal-viscoplastic constitutive equation, Johnson-Cook damage criterion for chip separation, and the modified Zorev's friction model can precisely predict the serrated chip formation in HSC without artificial assumptions. This advancement has removed the major barrier in the current machining investigations by numerical simulation. The present study also found that the tool rake angle has a significant effect on serrated chip formation. As the rake angle increases, the chip sawtooth degree and cutting forces decrease, but the chip segmentation frequency increases.