Mechanical response of shape memory alloy-based hybrid composite subjected to low-velocity impacts

One of the most common problems with composite materials is their low resistance to impacts with foreign objects because of their tendency to dissipate impact energy through internal delamination, weakening a large area of the structure. One of the possible solutions to increase impact resistance is to use of shape memory alloy wires in order to exploit their unique superelastic behaviour and the hysteresis that characterises their stress-strain curves. In this study, composite laminates were hybridised by embedding a network of shape memory alloy within the laminate structure and were subjected to low-velocity impact in order to analyse their response in comparison with a traditional composite. Ultrasonic C-scan analysis was undertaken on the samples after the impact in order to estimate the extension of the internal delamination. Results show that the shape memory alloy wires embedded in the laminate are able to absorb a large amount of energy, reducing the extension of the internal delamination.