形状记忆合金中的超弹性-对紧效应的实验和数值研究
1Department of Robotics and Mechatronics, Faculty of Mechanical Engineering and Robotics, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Krakow, Poland.
Materials (Basel, Switzerland)
|July 30, 2025
概括
紧固方法在拉力测试期间极大地影响形状记忆合金的行为. 一种新的杆杆抓力可以降低应力度,从而更准确地观察马氏体转变和超弹性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 形状记忆合金 (SMA) 具有独特的特性,如超弹性和形状记忆效应,对于智能材料至关重要.
- 它们的固态相位转换对施加的机械负荷和边界条件高度敏感.
研究的目的:
- 研究不同加载和紧方案对形状记忆合金非线性机械反应和相变化的影响.
- 为了比较标准紧方法与新型杆抓在减轻应力度方面的有效性.
主要方法:
- 使用两种不同的抓地配置 (标准和巨型) 对形状记忆合金样品的试验性拉力测试.
- 使用热成像和延伸度计在现场监测相位转换.
- 数字模拟来建模材料的非线性反应,并验证实验结果.
主要成果:
- 在拉力负荷下观察到形状记忆合金中明显的歇斯底里性质和超弹性行为.
- 证明,与标准抓相比,柱杆抓有效降低了局部应力度.
- 证实紧方案显著改变马氏体转变路径和应力-应变特征.
结论:
- 该研究阐明了在形状记忆合金中的边界条件,应力分布和相变化之间的复杂相互作用.
- 开发出来的螺杆抓地带提供了一个更可靠的方法来表征SMA行为,特别是马氏体转变.
- 结果为设计和应用工程中的形状记忆合金组件提供了关键的见解.
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