Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2019
Date : August 27, 2019 - August 30, 2019
The purpose of this study is to investigate numerically the static and dynamic characteristics of a shape memory alloy (SMA). In the previous study, we have proposed a vibration isolator using a post-buckled shape memory alloy, and pointed that it is expected to improve the isolation performance utilizing the negative tangent stiffness of post-buckled SMA and to mitigate the design requirement for the isolator. However, the mechanism and property of the negative tangent stiffness in post-buckled SMA, which is important for designing an isolator using post-buckled SMA, has not been clarified. Therefore, in this study, we investigate these characteristics by numerical analysis finite element method. Firstly, the static restoring force of post-buckled SMA was investigated. From the numerical result, the negative tangent stiffness of post-buckled SMA was observed and it was confirmed that the negative tangent stiffness arises when the phase transformation from austenite phase to martensite phase begins. The volume percent of martensite phase in post-buckled state was also clarified. Subsequently, the dynamic response of SMA was investigated. From this numerical result, it was confirmed that dynamically loaded SMA exhibited different behavior from that of general steel material.
