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三重连接分离主导纳米晶合金的稳定性

Annie K Barnett¹, Omar Hussein², Maher Alghalayini³

¹Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States.

|July 29, 2024

概括

金 (Pt-Au) 合金中的三连接 (TJ) 分离使颗粒边界不移动,防止粗. 这种TJ兴奋剂效应是纳米晶体Pt-Au材料热稳定的关键.

科学领域:

材料科学材料科学材料科学
纳米技术纳米技术
计算材料科学科学计算材料科学

背景情况:

纳米晶体材料提供了增强的性能,但容易发生颗粒粗.
溶液分离到粒度边界是已知的热稳定策略.
三连接 (TJs) 在合金稳定性中的特定作用仍然不太清楚.

研究的目的:

为了研究金 (Pt-Au) 纳米晶体合金中三连接 (TJ) 分离的现象.
量化确定TJ分离对这些合金热稳定性的贡献.
阐明TJ分离阻碍谷物粗化的机制.

主要方法:

大规模的原子模拟被用来建模Pt-Au纳米晶体合金.
模拟的重点是颗粒边界和TJs的溶液 (Au) 分离行为.
分析了溶液兴奋剂对谷物边界和TJs移动性的影响.

主要成果:

原子模拟证实了Pt-Au合金中的三连接 (TJs) 的显著溶液分离,与实验数据一致.
发现对TJs的分离是稳定纳米晶体Pt-Au合金对抗谷物粗化的主要因素.
通过溶液对TJs进行兴奋剂使它们变得不动,有效地锁定了谷物边界网络并抑制了其演变.
在稀释合金中,溶解物含量不足限制了颗粒边界和TJ分离在防止粗的有效性.

结论:

三连接 (TJ) 分离在纳米晶体Pt-Au合金的热稳定性中起着至关重要的作用.
通过溶解物兴奋剂对TJs的固定是防止谷物粗的主要机制.
准确预测纳米晶合金的行为需要明确考虑TJ分离效应,特别是在极端条件下.

关键词:

原子学模拟的原子学模拟谷物边界的谷物边界是什么纳米晶体材料是一种纳米材料.溶解物分离的分离方法三重交叉路口三重交叉路口三重交叉路口

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