Design and Analysis of a Superelastic SMA Damper

Based on the superelasticity of shape memory alloy (SMA), a superelastic SMA damper is designed, and its analytical model has been established and verified by experimental results. Numerical simulation is carried out to investigate the effects of the damper's parameters on its behaviors, such as groove depth, SMA wire amount, and friction coefficient, temperature and displacement amplitude. Results show that initial stiffness, external force, and dissipated energy of the SMA damper increase linearly with groove depth, SMA amount, and friction coefficient. Under different displacement amplitudes, the shapes of the external force—displacement curve of the damper are polygons, such as triangle, quadrangle, and pentagon, respectively, hence the SMA damper is a variable-stiffness type damper. In addition, experimental results indicate that the model can be used to simulate the mechanical behavior of the damper.