Novel process combined extrusion and severe plastic deformation for plate component with rib-web structure of magnesium alloys

Plates with rib-web structure of magnesium alloys are hardly to be fabricated through the conventional method. In this work, the variable circular channel angular extrusion (VCCAE) combined extrusion and severe plastic deformation is proposed, in which billet undergoes severe deformation at several variable circular angular channel. The FE model for VCCAE of scaling plate with ribs is established, and the experimental setup is designed. The feasibility of the novel process and the accuracy of the FE model are validated by simulations and experiments. Stress state and the effective strain distribution in the longitudinal section and cross section are analyzed. The results show that stress and strain distribution in the longitudinal section is extremely inhomogeneous and obvious stress concentration at the shear plane is founded. The microstructure in the angular region is more uniform and finer, which validate that the severe shear deformation induced by the angular channel in the VCCAE process could promote the deformation uniformity and grain refinement. The results of numerical simulation and experiments demonstrate that the VCCAE process proposed in this paper is feasible and it has great potential to manufacture high-performance plate with ribs.