Predictive Modeling of Flank Wear in Turning Under Flood Cooling

Abstract

The objective of this paper is to present physical and quantitative models for the rate of tool flank wear in turning under flood cooling conditions. The resulting models can serve as a basis to predict tool life and to plan for optimal machining process parameters. Analytical models including cutting force analysis, cutting temperature prediction, and tool wear mechanics are presented in order to achieve a thermo-mechanical understanding of the tool wear process. The cutting force analysis leverages upon Oxley’s model with modifications for lubricating and cooling effect of overhead fluid application. The cutting temperature was obtained by considering workpiece shear deformation, friction, and heat loss along with a moving or stationary heat source in the tool. The tool wear mechanics incorporate the considerations of abrasive, adhesion, and diffusion mechanisms as governed by contact stresses and temperatures. A model of built-up edge formation due to dynamic strain aging has been included to quantify its effects on the wear mechanisms. A set of cutting experiments using carbide tools on AISI 1045 steels were performed to calibrate the material-dependent coefficients in the models. Experimental cutting data were also used to validate the predictive models by comparing cutting forces, cutting temperatures, and tool lives under various process conditions. The results showed that the predicted tool lives were close to the experimental data when the built-up edge formation model appropriately captured this phenomenon in metal cutting.