Modelling the damage evolution in unidirectional all-carbon hybrid laminates

Hybrid reinforcements for composites have been extensively studied and adopted to overcome the lack of ductility via pseudo-ductility. Thin-ply all-carbon interlayer hybrid laminates have attracted attention for their peculiar pseudo-ductile tensile response. At the same time, conventional thick plies have been barely considered. This work developed a finite element model to simulate the complex tensile damage scenario of unidirectional thin- and thick-ply all-carbon interlayer hybrid laminates. The damage modes intended in the numerical model were fragmentation in the low-elongation (LE) plies, and delamination of LE and high-elongation (HE) ply interfaces. Thin- and thick-ply hybrid laminates were modelled and compared to available experiments. The numerical model was also adopted to simulate different layups to predict the effect of LE thickness fraction on the pseudo-ductile tensile behaviour and the evolution of damage modes. As suggested in the literature, the results allowed us to depict the damage mode map of the considered hybrid laminates. The map distinguishes the all-carbon hybrid laminate configurations with pseudo-ductile and brittle tensile responses.