A novel approach for assessing the wear status of a milling tool flank based on the entropy generation of friction and thermal conduction

Abstract

High-efficiency milling cutters are extensively used in the manufacturing industry due to their excellent cutting performance. However, milling vibrations lead to variation in frictional stress and frictional velocity at the tool-worker friction interface so the thermodynamic behavior of a cutter-worker friction system is complex and variable, this makes the wear prediction of the milling cutter’s flank face in the milling process difficult. In this paper. we first developed a model for transient cutting behavior under vibration; based on this, a model for transient contact friction between the flank face of a high-efficiency milling cutter’s teeth and the machining transition surface was developed, and the friction stress and friction velocity at the characteristic points of the flank face were solved with the help of simulation data. The structure of the frictional thermodynamic system of the flank face of the milling cutter teeth was decomposed, and the entropy generation model of friction force due to nonlinear friction variables in the process of high-efficiency milling under the tool offset and different contact angle positions due to milling vibration was developed, as well as the entropy generation model of the milling heat transfer process under frictional extrusion in the third deformation zone. Finally, the wear depth of the tool flank was predicted based on the thermodynamic entropy generation which were used as one of the input variables. The results showed that the relative prediction error of the prediction model was 1.7%, confirming the good accuracy of the prediction model.