Mechanical model and parameter analysis of superelastic SMA compound damper

The construction and working principle of a superelastic SMA compound damper is introduced. Based on the damper's mechanical behavior, its mechanical model is established. The effects of parameters such as the groove' depth of the inside slip block, friction coefficient between contact surfaces, the prestrain and amount of SMA wires, environmental temperature and displacement amplitude, on the damper mechanical behaviors are analyzed. The results show that, initial stiffness, export force and dissipated energy of the SMA damper increase linearly with groove' depth, SMA wire amount and friction coefficient. Under different displacement amplitude, the shape of the load-displacement curve of SMA damper is polygon such as triangle, quadrangle, pentagon etc, respectively. The SMA damper is a variable stiffness' damper. The yield displacement and export force of damper have linear increase with environmental temperature. Applying certain initial prestrain to SMA wires, the SMA compound damper becomes a friction type damper. In the end, compared with the experiment, the results obtained from the model are in good agreement.