A Simplified Spot Weld Model for Finite Element Analysis

Fatigue prediction of structures with a large number of spot welds requires simplified models for the spot welds. The simplified models should be able to deliver reliable stresses at the spot welds. This is actually still a challenge for the modeling techniques of spot welds. Based on recent research on the modeling techniques for spot welds and a nodal-force-based stress evaluation method, a simplified finite element model is developed for spot welds. The model can be applied to shell element models like automotive structures with coarse meshes and it is capable of delivering reliable stresses and stress intensity factors at spot welds which may be used for the fatigue predictions. The mesh-insensitivity of the model is also demonstrated.