Structural and damping performance of hybrid GFRP composites with thin sheet SMA inserts

This work explores a novel hybrid composite design that incorporates thin shape memory alloy (SMA) sheet inserts within glass fiber-reinforced polymer laminates. By using flat NiTi and Cu–Al–Mn alloy plates—instead of traditional SMA wires—the study evaluates whether increased material volume improves vibration damping. Brass inserts were also tested as a non-transforming control. The composites were subjected to free vibration, tensile, and flexural testing. NiTi inserts yielded the best damping and most consistent mechanical behavior. Cu–Al–Mn inserts showed potential as a lower-cost alternative but exhibited greater variability. Laser-cut patterns in NiTi inserts reduced damping slightly but enhanced flexural strength and interfacial adhesion. The findings underline how SMA type and insert design influence the balance between damping efficiency and structural performance.