2D FE Prediction of Surface Alteration of Inconel 718 under Machining Condition

Nickel-based super alloys such as Inconel 718 are widely employed in extremely hostile applications owing to their superior thermo-mechanical properties. On the contrary, these latter lead the industries to adopt conservative process parameters (e.g. low cutting speed) resulting in lower production rates. The possibility to increase the cutting parameters could lead to higher material removal rates and drastic reduction of the machining time of the process. The aim of this study is to investigate the effects of extreme cutting parameters on the surface and subsurface alterations such as grain size and hardness changes by developing a finite element (FE) numerical model. The Zener-Hollomon and Hall-Petch equation were implemented to predict the grain size and micro hardness variations due to the cutting process. In addition, the depth of the affected layer due to machining was predicted using the critical strain equation. The obtained results proved the accuracy and reliability of the proposed FE model showing a good agreement between the simulated and the experimental results.