Determination of Edge Fracture Limit Strain for AHSS in the ISO-16630 Hole Expansion Test

Abstract With the increased demand for application of sustainable materials and lightweight structures, sheet metal forming industry is forced to push existing limits. One area where this particular difficult when it comes assessing formability limit edges. For decades, ISO-16630 Hole Expansion Test (HET) has been standard expressing edge metals through Ratio (HER). However, in recent years, test criticized its high scatter results repeated experiments. This suspected be caused by operator-reliant post-processing test, or variations cutting conditions different specimens. study investigates impact shifting evaluation point from through-thickness crack onset surface failure on reported scatter, as well performs inverse modeling obtain an strain value.