Studies on a computational model and the stress field characteristics of weld-bonded joints for a car body steel sheet

Based on analyses of the local structure and hardness distribution of weld-bonded joints, a computational model composed of the base metal, the HAZ, the nugget and the adhesive layer is established. Both indentation and the inhomogeneity of the mechanical properties in joints are considered, an annular bonded surface area and a damaged adhesive zone also being taken into account. At the same time, discussions are made on a typical load–displacement curve of weld-bonded joints by the tensile shear test. Using the model established, stress fields of resistance spot welded joints and two types of weld-bonded joints which are made by adhesives with different elastic modulus have been given by the finite element method. In addition, the effect of the weld pitch on the stress and strain fields of two weld-bonded joints are investigated.