相关实验视频
Updated: Mar 16, 2026

05:04
Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
2.7K
在拉力负荷下分析-线的局部变形
概括
局部变形前线驱动-形状记忆合金中的马氏体变化. 转换界面的高剪压解释了通过同步射线衍射观察到的本地化行为.
科学领域:
- 材料科学
- 固体机械学
- 晶体学
背景情况:
- - (NiTi) 形状记忆合金经历应力诱导的马氏体变化.
- 这种转变的特点是局部变形前线的传播.
- 了解这些面的微力学对于预测材料的行为至关重要.
研究的目的:
- 为了研究围绕马氏体转化前线的奥氏体中颗粒溶解的弹性应变和应力.
- 阐明局部应力在转化局部传播中的作用.
- 确定单个粒度应力与宏观内部应力场之间的关系.
主要方法:
- 三维同步射线X射线衍射在微米级分辨率.
- 在压力下预训练线的现场成像.
- 有限元模拟以模拟局部变形和应力场.
主要成果:
- 在转化界面之前,奥氏体颗粒的局部应力发生了显著的改变.
- 鼻子形接口的高剪压与局部转换相关.
- 从粒级应力到宏观内部应力场的交叉观察到.
结论:
- 在NiTi中马氏体转化的局部性质是由转化界面的剪切应力所驱动的.
- 同步射线衍射为微机械应力分布提供了关键的见解.
- 有限元模型成功地合理化了应力场和转换前方拓的实验观测.
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