Experimental investigation and 3D simulation of machining of Inconel 718 for evaluation of thermal loads and depth of the affected layer

Distribution of thermal loads during the machining process leads to reducing the surface quality and rapid tool wear. Therefore, optimization of thermal loads in machining has always been important. On the other hand depth of the restructured layer can improve mechanical and metallurgical properties and of the workpiece. Since experimental investigation in machining operations is expensive and time-consuming procedure, finite element method is also used as an efficient tool in this regard. Therefore, at the first part of this study, experimental machining tests was carried on Inconel 718 alloy at the different cutting depth, cutting speed and the feed rate to measure machined surface temperature. The results of experiments were used to simulate machining process using commercial software of DEFORM-3D-V10. After calibration and validation of the results of 3D simulation with corresponding experiments, the effect of tool edge radius, tool nose radius, and workpiece hardness was investigated. To improve the accuracy of the simulations, heat transfer coefficient was calibrated by experimental result of temperature and it was defined as function of cutting parameters. Finally, the effect of machining parameters was investigated on the depth of the recrystallized layer using the critical strain criterion.