Evaluation and comparison of surface defects on a simplified model for the area around the fuel filler lid by simulation and experiments

There is a serious need in the automotive industry to predict surface defects in outer panels. Measures to prevent these defects can not be taken until a
test part has been manufactured. This costs a lot in time and money. Within the present project stamping tools for a model part resembling the area around the fuel filler lid was developed. This is an area of the outer surface of a car, which is particularly sensitive for surface defects. Based on this model both experiments and sheet-metal-forming simulations were performed and the results were compared. The result showed that the simulations were able to predict the location of the defects but the magnitudes of the defects were not sufficiently accurate. The defects that occurred were more like waves than small localised defects at the corners, “teddy bear ears”. These defects could be seen in both the experiments and the simulations.