在铁晶体内钻石纳米颗粒的内向运动
Yuecun Wang1, Xudong Wang2, Jun Ding2
1Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) & Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
Nature communications
|May 31, 2024
概括
固体纳米粒子在没有外力的情况下意外地沉入固体金属中. 这种新型的质量传输是通过沿着界面通道的原子扩散发生的,使得深入透.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 纳米技术 纳米技术
背景情况:
- 固体颗粒通常在没有机械负荷的情况下留在表面上.
- 了解粒子-固体相互作用对于材料工程至关重要.
研究的目的:
- 为了研究粒子在没有外力的情况下透到固体.
- 为了阐明这种不寻常的物质运输背后的机制.
主要方法:
- 在现场进行显微镜实验.
- 大规模的实验.
- 使用钻石纳米粒子 (~100nm) 和铁.
主要成果:
- 钻石纳米颗粒在高温下 (点的一半) 穿透铁到毫米深度.
- 粒子运动是位移性和全身运动.
- 一种局部应力,由铁原子通过界面通道扩散引起,驱动了运动.
结论:
- 在固体中展示了一种前所未有的质量运输方式.
- 这种机制不同于传统的原子扩散.
- 强调了界面现象在固态动态中的重要性.
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