Tool wear and heat transfer analyses in dry machining based on multi-steps numerical modelling and experimental validation
Résumé
In machining, tool–chip interface parameters such as pressure, temperature, sliding velocity and friction are extremely difficult to estimate only by experimental means. Theoretical methods can then give important solutions for predicting these quantities required for the assessment of tool wear. This work deals with a multi-steps modelling strategy based on several numerical calculations. The first step is a 3D thermomechanical analysis of the chip formation process. Cutting forces, chip morphology and chip flow direction as well as tool–chip interface parameters are obtained. The second step concerns the tool wear prediction using tool–chip interface parameters. The last step focuses on a 3D thermal analysis of the heat diffusion into the cutting tool using adequate thermal loading. An applied non-uniform heat flux is estimated using contact parameters obtained from the first step. Obtained results at each step of calculation are compared to experimental data. The predicted tool wear has been found in good agreement with experiments, and measured temperatures (using embedded thermocouples) very close to the temperature obtained by the last step of numerical calculation.