A physically based model of Ti6Al4V turning process to predict surface integrity improvements

In turning processes, surface improvements are strictly related to the physical phenomena induced by the involved thermo-mechanical loads. These phenomena are difficult to be analyzed while they occur, therefore the process simulation is a very important tool to deeply understand their evolution. Turning experiments were carried out on Ti6Al4V workpiece under different machining conditions. The microstructural modifications were analyzed in terms of metallurgical changes and micro-hardness. The physical mechanisms that occurred on the machined surface were investigated to construct a constitutive material flow model. The developed material model was implemented via sub-routine in a commercial FE software and validated through comparisons with experimental data (cutting forces, temperatures and microstructural modifications). The model was employed to predict the process variables of scientific interest (microstructural changes and surface improvement). The numerical results in main cutting forces, feed forces and temperatures prediction proved the accuracy and reliability of the proposed numerical model showing a good agreement with the experimental data.