Nonlinear Finite Element Analysis and Optimum Design of Spot-Welded Joints and Weld-Bonded Joints

Abstract

Resistance spot welding and hybrid weld bonding have wide applications in the body work construction within the automobile industry. The integrity of the spot welds and applied adhesives determines the body assembly rigidity and dynamic performance. Incorporating contact nonlinearity and geometric nonlinearity, finite element analysis (FEA) have been carried out to investigate the structural stiffness and strength of both spot-welded and weld-bonded assemblies. Topology optimization has been performed to reveal the distributions of material effectiveness in the overlap regions and suggest a feasible method for removing underutilized material for weight reduction. Design optimization has been conducted with an aim to reduce the maximum von Mises stress in the assembly to minimum by choosing optimum values for a set of design variables, including the weld spacing, weld diameter and overlap width.