Fishing line artificial muscle reinforced composite for impact mitigation and on-demand damage healing

Abstract

In this study, a fishing line artificial muscle reinforced syntactic foam composite was investigated. About 3.5 vol.% of polymer artificial muscle was woven into a two-dimensional grid skeleton and embedded into a syntactic foam matrix. The grid-stiffened syntactic foam composite was designed to be able to repeatedly heal cracks on-demand. Short thermoplastic fibers were also dispersed into the foam matrix both as reinforcement and as a healing agent. The composite panel was repeatedly impacted, bending fractured, and healed as per the biomimetic close-then-heal strategy. It is found that the composite panel responds to impact quasi-statically. The impact- and bending-induced macroscopic cracks can be repeatedly healed with high healing efficiency, under both free and clamped boundary conditions. Contrary to most healing systems, the healing efficiency within the damage–healing cycles in this study increases as the damage-healing cycle increases. Because the artificial muscle is made of low-cost and high-strength fishing line, it is envisioned that the composite panel developed in this study may be a viable alternative core for healable lightweight composite sandwich structures at competitive cost.