Axial Compressive Behavior of Single-stage Bellows of TiNi Shape Memory Allov for Seismic Applications

摘要

The bellows formed of TiNi shape memory alloy (SMA) is proposed as a new type of seismic protection device. The bellows structure is known to have lower rigidity along the axial direction through effect of its shape. TiNi is known to be one of the most typical SMAs, which have high damping characteristics for dynamics engaged in its twin formation under martensite state and have the ability to recover completely from the large strain after unloaded and or heated. In this study, fundamental compressive behavior of TiNi bellows was investigated and discussed. Several shapes of TiNi single-stage bellows produced by rubber bulge method were prepared. They were heat-treated for some heat treatments and then examined on compression tests. Based on the results, the relationships among the bellows shapes and the stiffness, energy-absorbing capacity and so on were clarified. Finally, it was found from these results that single-stage bellows of TiNi SMA could be used as one of seismic protection devices.