Enhancement of Spot Weld Modeling using MAT_100_DAI

During the recent years, the development of suitable and robust models for joining technologies has been advanced to augment the quality of full car crash simulations. Furthermore, the utilization of high-strength steel alloys and sophisticated joining concepts has led to an increased importance of joints in simulations. On the basis of a fracture energy criterion, the bi-linear, elasto-plastic material model MAT SPOTWELD DA which already includes a stress based failure criterion will be enhanced to model the post failure behavior more precisely. Particularly, in complex structures with a series of joints at a flange, e.g. spot welds or rivets, the post failure behavior of the joints can control the overall behavior during crash. This new criterion has been implemented into LS-DYNA. In combination with the new possibilities in modeling single joints, the effects of the new options are validated and investigated on the basis of coupon as well as of component level.