ON THE MODELLING OF AN ALUMINIUM ALLOY MILLING: 3D FEM APPROACH
Keywords: Milling modelling, FEM, Jhonson-cook material model, A2024-T351
AbstractThe present contribution put forwards a 3D FE approach to perform a parametric study on the effects of depth of cut and cutting speed on surface and chip mor-phologies, for machining an aerospace grade aluminium alloy A2024-T351.The ultimate objective is to improve the comprehension of chip formation phenomenon during rough to finish down cut milling process. Numerical inves-tigations have been realized in two successive steps. Pri-marily, a 3D model for rough cut machining has been de-veloped. Simulation results of later model were compared with the experimental ones. Onwards, numerical models for semi-finish to finish cutting cases were established. It was found that, workpiece nodal displacements along depth of cut are higher for finish cutting operations. This represents an increased percentage of volume under inelastic deformation, resulting in higher energy dissipation. Furthermore, it was numerically found that at higher cutting speeds material strengthens, due to strain rate hardening phenomenon. These strengthening phenomena results in continuous chips and fine quality surface topologies in finish cutting operations, performed at higher cutting speeds.