Studies on the Efficiency of LS-DYNA in Sheet Metal Stamping for Feasibility and Formability Analyses

Feasibility and formability analyses serve different purposes in automotive panel designing. The turnaround cycle of forming simulation is essential, since the designs change very frequently in early stage of vehicle development. The goal of this study is to evaluate the feasibility by using LS-DYNA ® as an alternative to Autoform for both early product evaluations, as well as more detailed formability analysis in GM’s production developments. Targeting the requirements of feasibility and formability analyses, the key techniques of using LS-DYNA® in sheet metal forming simulations are systematically studied, such as element formulation, material model, adaptive meshing, and mass scaling, etc. The study shows that the simulation time is able to be significantly reduced by choosing proper combination of the numerical parameters, while the accuracy of the results remains satisfying. In this study, 21 production developments by Autoform were translated to LS-DYNA so that they could be run using the LS-DYNA solver on GM’s HPC server. These 21 parts encapsulate all three engineering modules and contain a wide variety of parts. Given the computational resources available in GM, the simulation time and results by LS-DYNA are competitively comparable to Autoform.