符合格子调制使Ni-Mn-Ga马丁石的异常弹性成为可能
Kristýna Repček1, Pavla Stoklasová1, Tomáš Grabec1
1Institute of Thermomechanics of the Czech Academy of Sciences, Prague 8, 18200, Czech Republic.
Advanced materials (Deerfield Beach, Fla.)
|August 12, 2024
概括
在Ni-Mn-Ga铁磁形状记忆合金中,双边界的移动性与强大的晶格剪切弹性不稳定性有关. 这种由格子调制驱动的不稳定性,解释了10M马氏体中双边界的独特高流动性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固体力学 固体力学是什么
背景情况:
- 铁磁形状记忆合金,特别是基于Ni-Mn-Ga的合金,具有很高的双边界流动性.
- 对于调制马丁岩石中这种移动性负责的底层格子机制仍然不太了解.
- 了解这种现象对于推进磁力机械应用至关重要.
研究的目的:
- 在调制的Ni-Mn-Ga马丁石中阐明双边界的高流动性背后的格子机制.
- 确定将Ni-Mn-Ga与其他马氏体合金区分开来的特定特征.
- 为了实验验证关于格子行为的理论预测.
主要方法:
- 采用了激光-超声波测量,包括过渡格子谱学和基于激光的共振超声谱学.
- 研究了分层结合的五层调制 (10M) Ni-Mn-Ga 晶体.
- 将实验结果与第一原则计算进行了比较.
主要成果:
- 在10M Ni-Mn-Ga的网格中证实了显著的剪切弹性不稳定性.
- 观察到的不稳定性强度超过了其他马氏体材料和理论预测.
- 建立了格子不稳定性和观察到的格子调制之间的直接相关性.
结论:
- 10M Ni-Mn-Ga 的非凡双边界流动性归因于调制序列的动态断裂的晶格尺度机制.
- 这种机制与观察到的强剪弹性不稳定性直接相关.
- 这些发现为Ni-Mn-Ga合金的独特特性提供了基本的理解.
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