Cohesive-zone modeling of the deformation and fracture of weld-bonded joints

In previous work, cohesive-zone models have been developed separately for the analysis of adhesively bonded joints and for the analysis of spot welded joints. The appropriate fracture parameters have been determined for a commercial rubber-toughened epoxy for bonding thin sheets of 5754 aluminum alloy. Fracture parameters have also been determined for spot welds formed under specific processing conditions with this same alloy. It has been established that these parameters provide a predictive capability for design, in the sense that loads, deformation, and energy absorption can be consistently predicted for different geometries of joints bonded under nominally identical conditions. In the present paper, these two separate models are combined too provide a design tool for weld bonding in which adhesive technology is combined with spot welding. It is demonstrated that the models developed separately for the two joining techniques can be combined and used with no further modification to predict the behavior of weld-bonded geometries. In particular, the strength and energy-absorption characteristics of a joint from initial loading through final failure are reproduced for the two different geometries investigated.

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