Bio-inspired laminate design exhibiting pseudo-ductile (graceful) failure during flexural loading

Discontinuous reinforcement phases are often observed in high toughness natural materials, for example, nacre. The aim of this study is to introduce a degree of 'pseudo-ductility' to fibre reinforced polymer materials by exploiting such discontinuities. The work presented aims to take a simple concept of discrete material sections and apply it in the form of ply cuts in a carbon fibre reinforced polymer. A variety of specimen types which encompass the principles inspired by the architecture of nacre were tested in four point bend flexure and the failure processes investigated. Finite element analysis was also carried out to understand stress conditions around ply cuts and their role in the observed failure. It was observed that ply cut spacing and ply cut density were important parameters in achieving 'pseudo-ductile' failure.