Development of a multi-scale and coupled cutting model for the drilling of Ti-6Al-4V

Abstract The present paper investigates the thermo-mechanical loading involved in hole drilling of Ti-6Al-4V. Indeed, the heat and strains developed in a very restricted area at the tool vicinity are responsible for various undesired side effects among which: tool damage, residual stresses, poor surface roughness, and metallurgical alterations. The confined nature of the drilling process prevents from any experimental access to some governing physical data such as local strain fields and local energies. Therefore a mixed numerical-experimental approach is herein proposed in order to provide local in-sight to essential tool-related thermal and mechanical sources. It relies on strain and temperature measurements at various locations of the cutting edge that are used to validate a multi-scale numerical model. This latter is then used to assess the energy budget involved in the material removal. The presented results prove the ability of such technique in obtaining valuable information on the in-process generated heat and the way it spreads within the workpiece and beyond. Results also show the spatial heterogeneity of the cutting phenomenon along the cutting edge and highlight the complexity of defining optimal cutting parameters and optimal tool design.