Shape memory alloy flexures
Shape memory alloy flexures
复制标题
形状记忆合金弯曲件
DOI：
10.1016/j.msea.2003.12.062
复制
发表时间：
2004
期刊：
影响因子：
6.4
通讯作者：
R. Clavel
中科院分区：
文献类型：
--
作者：
Y. Bellouard;R. Clavel
柔性用于精密工程，其中高精度，无磨损，平滑和可重复的运动是必需的。弯曲是基于材料的变形来实现弹性连接部件之间的运动。它们用于各种精密机构，如高分辨率天平或高精度光学定位台。形状记忆合金（SMA）是设计柔性件的一种有吸引力的选择。超弹性挠曲可以承受更大的变形相同重量的传统挠曲。此外，SMA的阻尼特性可通过相变控制，为自适应柔性机构的设计提供了新的机会。马氏体相变也可以用来改变弯曲的固有频率，增加有用的功能，如抗振。本文介绍了基于非线性梁理论的SMA挠曲设计原则。结果表明，实测数据与预测数据吻合良好。此外，还给出了相变对阻尼性能影响的实验结果。在使用r相变的体微机械弯曲中观察到固有频移和阻尼增加。这些结果证明了固有频率可调挠性的可行性。
Flexures are used in precision engineering where highly accurate, wear-free, smooth and repeatable motion is desired. Flexures are based on deformation of material to achieve a motion between elastically joined parts. They are used in a variety of precision mechanisms such as high-resolution balances or high accuracy optical positioning stages. Shape memory alloys (SMA) are an attractive option in designing flexures. Superelastic flexures can withstand larger deformations for the same weight as a conventional flexure. In addition, the damping properties of SMA, controllable through the phase transformation, offer new design opportunities for adaptive compliant mechanisms. The martensitic phase transformation can also be used to shift the natural frequency of flexures adding useful functionalities such as vibration rejection. This paper presents design principles of SMA flexures based on non-linear beam theory. Results show a good agreement between measured and predicted data. In addition, experimental results on phase transformation effects on damping behavior are also presented. Both, natural-frequency shift and increased damping were observed in bulk-micro machined flexures using the R-phase transformation. These results demonstrate the feasibility of natural-frequency-tunable flexures.