Predictive models for flank wear in near dry machining

The objective of this paper is to present a methodology to analytically model the tool flank wear rate in near-dry turning. The resulting models can serve as a basis to minimize time-consuming machining tests in predicting tool life. Analytical models, including cutting force model, cutting temperature model, and tool wear model, are presented. The cutting force model was established based on Oxley's model with modifications for lubricating and cooling effect due to the air-oil mixture in near-dry machining. The cutting temperature was obtained by considering a moving or stationary heat source in the tool. The tool wear model contained abrasive mechanism, adhesion mechanism, and diffusion mechanism. The important factors related to this model were contact stresses and temperatures that were obtained from the cutting force model and the cutting temperature model. To develop these models, a set of cutting experiments using carbide tools on AISI 1045 steels were performed to calibrate the coefficients in the models and to verify the proposed flank wear mechanisms. The comparisons between the model-predictive flank wear and experimental results showed that the flank wear in near dry machining can be estimated well by the proposed models. It was also found that the cutting velocity was a dominant factor among the cutting conditions.