A Framework for Modeling Spot Welds in Finite Element Analysis of Auto-Body Structures

In this paper, a generalized spot weld model is presented for analyzing various performance attributes of spotwelded automotive structures. The spot weld model employs conventional definitions of beam- or nonlinear spring type elements. The relevant global mechanical properties are presented in the form of six pairs of generalized load-displacement relationships with respect to six degrees of freedom. The required generalized load-displacement relationships can be readily derived with assistance of local finite element welding process model along with limited single-weld coupon testing. As result, the effects of actual weld properties, welding-induced residual stress states, etc. can be incorporated for applications in finite element analysis of complex autobody structures. Its applications in conventional stress analysis for durability prediction, and limit load prediction, and crashworthiness simulation are also discussed with a few selected examples.