Failure Characterization of Multi-Alloy and Multi-Gauge Hot-Stamped Tailor-Welded Blanks

Abstract

To increase the ductility of hot-stamped structural components, the use of tailor-welded blanks (TWBs) of both high-strength and ductile steels has recently drawn attention. In this study, the failure behavior of the hot-stamped tailor-welded blanks (TWBs) comprising steel sheets of Ductibor®500-AS laser-welded to Usibor®1500-AS was investigated. TWBs with different combinations of 1.2 mm- and 1.6 mm-thick parent metals were hot-stamped and then tested under uniaxial-tension and equi-biaxial-tension loading conditions. Under longitudinal uniaxial-tension loading, all of the TWB types failed in the Usibor®1500-AS whereas in transverse uniaxial-tension loading, the failure occurred in the Ductibor®500-AS. Furthermore, in the equi-biaxial-tension tests, the 1.2 mm-1.6 mm TWBs presented the highest strains prior to failure, while fracturing in the Ductibor®500-AS sheet.