Shape Memory Alloy Damper Research Articles

Development of a Shape Memory Alloy Damper for Intelligent Bridge Systems

The application of intelligent materials with self-repairable and self-diagnosis functions will provide more efficient and effective earthquake protective system to bridge structures. Shape memory alloys are possible candidates of intelligent materials that are applicable to bridge structures. The damping device made of shape memory alloys was proposed in this paper. The damping device that was simple Nitinol plate can absorb seismic energy and reduce the seismic force by its pseudo yield effect. This study focuses on the damping enhancement effect of the device to bridge structures. A series of shaking table test was carried out in order to verify the damping enhancement effect under earthquake type excitations. As a result of this study, it is found that the Nitinol plate damping enhancement device can reduce the seismic response of the bridge structures and can perform its function more efficient and effective when in shape memory phase.

Mechanical damping of rapidly quenched TiNiCu alloys

Among intermetallic compounds, the shape memory alloy is generally characterized by a unique shape memory phenomenon, high strength and high damping. The high damping of shape memory alloys may be closely related to the thermomechanical internal friction caused by the dynamic interferences in the heavily developed twin martensites. In the present paper, we investigate the possibility of improvement of the mechanical damping in rapidly quenched melt-spun Ti 50Ni 50− x Cu x ( x = 0–15 at.%) alloys. Mechanical damping was increased clearly with increase in cooling rate, in which microstructures were changed from coarse dendrite to very fine columnar grains. Furthermore, the mechanical damping was also increased by a 973 K aging treatment.