Active repair of self-healing polymers with shape memory alloy wires

We report the first measurements of self-healing polymers with embedded shape memory alloy (SMA) wires. Improvements of healed peak loads by up to a factor of two are observed, approaching the performance of the virgin material. Moreover, the repairs can be effected with reduced amounts of healing agent. The improvements in performance of self-healing polymers with SMA wires are due to three effects: i) crack closure, which reduces the crack volume, ii) heating of the curing agent during polymerisation, which improves the cross-linking, and iii) mechanical registration of the two crack faces, which results in a reduced crack volume on closure.