An eulerian finite-element model for determination of deformation state of a copper subjected to orthogonal cutting

An Eulerian finite-element (FE) model was developed to predict the stress and strain distributions in the material subjected to the orthogonal machining process. Metallographic sections taken from commercially pure copper samples and subjected to orthogonal cutting were examined to determine the local strain gradients generated in the material ahead of the cutting tool tip. Local flow stress values were estimated from the microhardness measurements. Experimental flow stress and equivalent plastic strain values were found to obey a Voce-type exponential relationship, which was used in the development of the material model for the numerical simulations. The sizes of both the primary deformation zone (350 µm) and the secondary deformation zone (50 µm) predicted by the numerical model were in agreement with the experimental observations. The experimental results showed that the equivalent strain was 3.65 in the material 50 µm directly ahead of the tool tip, which compared well with the numerically observed strain (3.50). According to the numerical observations, along the primary shear plane, the high tool tip stress of 410 MPa decreased to 260 MPa near the chip root. Numerical and experimental stress and strain distributions correlated well in terms of both magnitudes and distributions, indicating that the application of an Eulerian FE approach served to predict the deformation state of the material ahead of the tool tip successfully.