Abstract

Owing to the dissipative phase transformation and the porosity characteristics, cellular shape memory alloy (SMA) shows high damping capacity and thereby superior performance in vibration control. This paper studies the damping capacity and vibration behavior of the cellular SMA by means of the unit-cell finite element method. A material model of dense SMA is employed to simulate the thermodynamic behavior of the cellular SMA. A loss factor ω is introduced to evaluate the damping capacity of cellular SMA in a successive loading-unloading cycle. The effects of the material properties (the stress difference between the forward and reverse transformations, the saturated value of the transformation strain), the ambient temperature and the pore morphology (the porosity and the axial ratio of spheroid pore) on the damping capacity are investigated. Besides, the cellular SMA with randomly distributed pores is also considered. Simulation results well demonstrate the high damping capacity of the cellular SMA due to the local dissipative martensite phase transformation. Finally, by comparison of the free vibration behavior between the cellular SMA beam and the elastic beam, the cellular SMA exhibits superior performance in vibration control.

摘要

由于耗散相变和孔隙率特性，蜂窝形状记忆合金（SMA）显示出高阻尼能力，从而在振动控制方面表现出优异的性能。本文采用单胞有限元法研究了蜂窝SMA的阻尼能力和振动行为。采用致密 SMA 的材料模型来模拟蜂窝 SMA 的热力学行为。损耗因子ω引入以评估蜂窝SMA在连续加载-卸载循环中的阻尼能力。研究了材料特性（正反相变应力差、相变应变饱和值）、环境温度和孔隙形态（球状孔隙的孔隙率和轴比）对阻尼能力的影响。 . 此外，还考虑了具有随机分布孔隙的蜂窝状 SMA。由于局部耗散马氏体相变，模拟结果很好地证明了蜂窝 SMA 的高阻尼能力。最后，通过比较蜂窝SMA梁和弹性梁之间的自由振动行为，蜂窝SMA在振动控制方面表现出优越的性能。