Elastic-plastic finite element analysis of automotive body panel stamping processes using dynamic explicit time integration scheme

In this article, the elastic-plastic finite element formulations using dyna mic explicit time-integration schemes are proposed for numerical analysis o f automotive body panel stamping processes. A general formulation of finite element simulation for complex sheet forming processes with arbitrarily sh aped tools is briefly introduced. In finite element simulation of automotiv e body panel stamping processes, the robustness and stability of computatio n are important requirements since the computation time and convergency bec ome major points of consideration besides the solution accuracy due to the complexity of geometry and boundary conditions. For analyses of more comple x cases with larger and more refined meshes, the explicit method is more ti me effective than the implicit method, and it has no convergency problem an d has the robust nature of contact and friction algorithms, although the im plicit method is widely used because of excellent accuracy and reliability. The elastic-plastic scheme is more reliable and rigorous, while the rigid- plastic scheme requires short computation time. The performance of the dyna mic explicit algorithms is investigated by comparing the simulation results of forming of complex-shaped automotive body parts, such as a fuel tank an d a rear hinge, with the experimental results. It has been shown that dynam ic explicit schemes provide quite similar results to the experimental resul ts. It is thus shown that the proposed dynamic explicit elastic-plastic fin ite element method enables an effective computation for complicated automot ive body panel stamping processes.