Rate dependent free energy formulations for dynamically excited superelastic SMA wires
Rate dependent free energy formulations for dynamically excited superelastic SMA wires
复制标题
动态激发超弹性 SMA 线的速率相关自由能公式
DOI：
10.1002/pamm.202000209
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Klinkel S.
中科院分区：
文献类型：
--
作者：
Kaup A;Altay O;Klinkel S.
超弹性形状记忆合金（SMA）是一种金属两相多晶合金。奥氏体和马氏体相之间的转变使超弹性SMA具有独特的滞后能量耗散能力，这对于开发新型结构智能振动控制系统特别有趣。然而，在结构控制中，大多数振动发生在高应变率区域，这会干扰自生热的释放并导致原子晶格失稳，从而影响滞后耗散。本工作提出了两种不同的应变率相关的自由能公式，旨在提高现有的SMA丝的一维宏观模型的准确性。这些方法是在不同的连续热机械框架中开发和实施的，而不会损害解决方案过程的简单性和鲁棒性。第一种方法引入了一个额外的控制变量的熵演化。第二种方法使用的潜热演变的现象学制定。通过对SMA丝进行循环拉伸试验，验证了所提出的配方。结果表明，采用新公式计算能更准确地反映SMA丝的超弹性响应。
Superelastic shape memory alloys (SMAs) are metallic two‐phase polycrystal alloys. The transformation between austenite and martensite phases allows superelastic SMAs unique hysteretic energy dissipation capacity, which is particularly interesting for the development of new‐type of intelligent vibration control systems for structures. However, in structural control, most of the vibrations occur in high strain rate regimes, which interfere the release of self‐generated heat and cause atomic lattice destabilization and thus influence the hysteretic dissipation. The present work proposes two different strain rate dependent free energy formulations and aims to improve the accuracy of existing one‐dimensional macroscopic models of SMA wires. The approaches are developed and implemented in different continuum thermomechanical frameworks, without impairing the simplicity and robustness of the solution process. The first approach introduces an additional control variable for the entropy evolution. The second approach uses a phenomenological formulation of the latent heat evolution. The proposed formulations are validated by cyclic tensile tests conducted on SMA wires. The results show that the calculations using the new formulations can represent the superelastic SMA wire response more accurately.
影响因子：
4.1
作者：
Kaup, A.;Altay, O.;Klinkel, S.
通讯作者：
Klinkel, S.