Abstract
In this study an effect of the hole in the car body structure on the strength and the countermeasures by adding a flange to the hole edge were experimentally examined. The corner is not damaged by the hole, and the maximum load decreases even if a plane surface equivalent to Karman's effective width is left. It was demonstrated that the decrease in maximum load can be suppressed by setting a short flange on the hole edge. In addition, we examined the clarification of the flange shape that achieves both formability and performance using FEM analysis, and confirmed that even a flange with a formable shape has a strength recovery of 100％.
