Interactions between propagating cracks and bioinspired self-healing vascules embedded in glass fibre reinforced composites

This study considers the embedment of a bioinspired vasculature within a composite structure that is capable of delivering functional agents from an external reservoir to regions of internal damage. Breach of the vascules, by propagating cracks, is a crucial pre-requisite for such a self-healing system to be activated. Two segregated vascule fabrication techniques are demonstrated, and their interactions with propagating Mode I and II cracks determined. The vascule fabrication route adopted played a significant role on the resulting laminate morphology which in-turn dictated the crack–vascule interactions. Embedment of the vascules did not lower the Mode I or II fracture toughness of the host laminate, with vascules orientated transverse to the crack propagation direction leading to significant increases in GI and GII through crack arrest. Large resin pockets were found to redirect the crack around the vascules under Mode II conditions, therefore, it is recommended to avoid this configuration for self-healing applications.