Toughened high performance epoxy resin system for aerospace applications

The present study describes the results of a detailed investigation of the fracture toughness and fatigue crack growth behaviour of epoxy resins used for aeronautic applications. More specifi cally, the infl uence of incorporating thermoplastic or triblock copolymers to neat resin in order to increase the toughness is evaluated. The experimental results deduced from static as well as dynamic loading conditions highlight the varying degree of effectiveness of the chosen toughening approaches. In combination with electron microscopic analysis of the fracture surfaces, the basic structure-property relationships and deformation mechanisms are presented and the different strategies to improve the fatigue behaviour are discussed.