An experimental study on the crack initiation from notches connected to interfaces of bonded bi-materials

A systematic experimental study was conducted to investigate the interaction between cracks, notches and interfaces of bonded aluminum and polymer joints. Bi-material specimens with sharp V-notches with variation in notch angles (30°, 90° and 120°), bonding strengths and loading locations were tested under three-point bonding. The notch angle and the bonding strength have significant effect on the crack initiation load. For weakly bonded polymer/metal specimens, crack initiation load increases with the increase of the notch angle. The loading point locations also affect the crack initiation load due to change in local mode-mixity at the notch tip.