FEM Analysis on Deformation of Coupled Process

This research focuses on investigating major imperfection in coupled processes of ““Welding-to-Forming”” and “Forming-to-Welding” which are frequently found in parts production in automotive industries. Finite Element Method (FEM) based Virtual Manufacturing (VM) approach is used to predict final dimensional change in both welding and forming processes through the utilization of specialized FEM software Simufact.Welding and Simufact.Forming. This research is to demonstrate the accuracy in predicting final geometry in both coupled processes where the physical properties from the first process serves as the initial condition for the later process. Low carbon steel S235 with thickness of 2 mm along with filler material ER70s mild steel is selected as material for both coupled process simulations. This study incorporates thermo-mechanical FEM as the solver for computational process as well as assign Goldak’s Double Ellipsoid Heat Source model on welding simulation that serves as moving heat source, while in forming process, a sheet metal bending process with hydraulic press is incorporated. For each coupled process, the result of the first manufacturing process will be transferred with legitimate procedure proposed by Simufact software and will serve as the initial condition for the subsequent manufacturing process. The FEM-based VM simulation was successfully conducted for both coupled process and shows in simulation result, that the average final displacement due to spring-back effect on coupled processes of “Welding-to-Forming” is 1.52 mm, while on “Forming-to-Welding” simulation results, the average final distortion yields the value of 1.12 mm.