An experimental and finite element investigation of chip separation criteria in metal cutting process

Chip separation is an important issue in finite element method (FEM)-based simulation of the cutting process owing to its significant impact on the predicted chip formation, as well as on the temperature and stress distributions. Typically, the chip separation criteria and the arbitrary Lagrangian–Eulerian (ALE) method have been utilized in chip formation simulations. This study aimed to evaluate the chip separation criterion and the ALE method in terms of chip formation, cutting force, cutting temperature, and stress distribution. Particularly, the effective plastic strain criterion and the failure-zone-assisted and ALE methods were utilized to model the orthogonal cutting of Inconel 718 alloy. Furthermore, experimentations were performed, and the results of FEM predictions were compared with the experimentally measured results. In general, ALE method was more consistent with the experiment. The ESPC method does not seem to handle chip shape and cutting temperature well, while the FZA method may not be suitable for predicting surface stress due to the deformation and failure of the material concentrated in the fail assist area.