Relation between stress intensity factor of circumferential crack and adhesive thickness in bonded round bar

The fracture of the bonded dissimilar materials generally occurs near the interface or at the interface edge. In this study, the stress intensity factors of the circumferential crack near the interface and the circumferential interface crack are analysed by the crack tip stress method. The relation between the dimensionless stress intensity factor of the circumferential crack and the adhesive thickness is investigated. The dimensionless stress intensity factors are defined by using the singular stress value at the crack tip point in bonded round bar without crack. The dimensionless stress intensity factors based on the singular stress value become constant irrespective of the adhesive thickness. In addition, the dimensionless stress intensity factor of the circumferential crack in bonded round bar is compared with that of the edge crack in bonded plate. Both factors coincide with each other when the geometrical condition and material combinations are the same. (paper)