Fracture characterization of interfacial cracks with frictional contact of the crack surfaces to predict failures in adhesive-bonded joints

Anisotropic/isotropic interfacial cracks with frictional contact along bi-material interfaces are investigated to predict the load-bearing capacity of adhesive-bonded joints. An asymptotic solution for an interfacial crack in an anisotropic/isotropic bi-material is presented. The adhesion strength of composite/steel bonding is evaluated in terms of the energy release rate of an interfacial crack and the fracture toughness of the interface. The applicability of the finite crack-extension strain-energy release rate is validated by comparing the critical finite extension energy release rate of double-lap joints with the measured fracture toughness from bi-material end-notched flexure tests, and the asymptotic solution is compared with finite element analysis results to investigate the range of applicability.