单晶金属微立方体中的梯度纳米结构的动态产生和演变
Ramathasan Thevamaran1, Olawale Lawal2, Sadegh Yazdi2
1Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA. thevamaranr@rice.edu elt@rice.edu.
概括
高速冲击在银微立方体中动态地产生极端梯度的纳米结构. 这些转变为开发具有高强度和强度的先进金属提供了新的途径.
科学领域:
- 材料科学
- 纳米技术
- 机械工程
背景情况:
- 单晶银微立方体是使用自下而上的种子生长方法合成的.
- 了解极端条件下的物质行为对于先进的工程至关重要.
研究的目的:
- 研究极端梯度纳米结构的动态产生和静态演变.
- 探索银微立方体中的变形机制,
主要方法:
- 合成几乎没有缺陷的单晶银微立方体.
- 使用激光诱导弹弹撞击测试以以超音速 (~400 m/s) 发射微立方体.
- 分析了对不可穿透的基板造成的纳米结构变化.
主要成果:
- 证明了极端梯度纳米结构的动态形成和静态演变.
- 由高应变率,应变梯度和再结晶驱动的显著纳米结构变化.
- 透露了受晶体和样品形状对称性的变形机制.
结论:
- 高速冲击在金属中有效地产生渐变纳米粒度结构.
- 这些纳米结构转变显示出开发高强度,高度金属的潜力.
- 这些发现支持在需要优质材料性能的航空零部件中的应用.
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