Abstract
The failure behaviour around a crack tip in adhesive joint is important in relation to the structural integrity of adhesive structures. The bond thickness is one of the important design parameters in adhesive structures. In this study, we investigate the bond thickness effect on the fracture toughness of adhesive joint using rubber-modified epoxy resin from the viewpoint of microstructure. The shapes of dispersed rubber particles in adhesive layers of damaged and undamaged specimens are observed by an optical microscope. As a result, damage zones along interfaces between an adhesive layer and two adherends influence the fracture toughness of an adhesive joint which has a thin bond thickness
