Mode-I fracture of CFRP composite bonded joints: Influence of surface treatment and adhesive ductility

Composite materials are increasingly being used for structural applications in the aircraft industry, for example, wings and fuselages, because of their superior damage resistance and excellent stiffness to weight ratio [1, 2]. Carbon fiber reinforced polymer (CFRP) composites with improved mechanical properties allow structural design to displace the more conventional materials, aluminum and titanium alloys, for primary structures [3]. For example, in the design of modern commercial aircraft such as the Boeing 787, advanced composites (50% by weight) are replacing conventional structural materials [4].