ABSTRACT

Adhesive joints are increasingly being used due to their improved mechanical performance and a better understanding of the mechanics of failure. To predict the joint strength, one must have the stress distribution and a suitable failure criterion. The stress distribution can be obtained by a finite element analysis or a closed-form model. This chapter focuses on stress–strain-based models but a mention should be made to fracture mechanics-based approaches. For example, the resistance to crack propagation in an adhesive bondline can be quantified in terms of the critical energy release rate, GC. T. Wah was the first to consider laminated composite adherends. The laminated adherends were symmetrical about their midsurface. Using a joint with a relatively flexible adhesive layer, D. Chen and S. Cheng concluded that the peak shear stress in the adhesive is not at the end of the overlap but at a distance of 20% the adherend thickness.