结收缩动力学和表面树突生长在外太空中漂浮的耐火合金滴滴
Haipeng Wang1, Hui Liao1, Liang Hu1
1School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an, 710072, China.
Advanced materials (Deerfield Beach, Fla.)
|March 10, 2024
概括
中国空间站的微重力实验揭示了耐火合金中独特的冷收缩和树突生长. 减少对流允许新的3D树突生长模式,促进合金固化理解.
科学领域:
- 材料科学 材料科学 材料科学
- 固化科学 固化科学
- 微重力研究 微重力研究
背景情况:
- 冷收缩和树突生长显著影响合金微观结构和加工.
- 在微重力下研究这些现象至关重要,但由于地球上的对流,这也具有挑战性.
- 了解在减轻重力条件下的固化对于先进材料开发至关重要.
研究的目的:
- 研究微重力下的耐火合金中冷收缩和树突增长的动态.
- 探索减少对流对合金固化行为的影响.
- 揭示空间中新的微观结构模式和生长机制.
主要方法:
- 在中国空间站 (10^-5 g0) 进行的轨道固化实验.
- 使用的Nb82.7Si17.3和Zr64V36耐火合金具有高温 (高达2265K) 和显著的低冷却.
- 采用微重力滴滴凝固的模拟来分析接口迁移,温度梯度和流场.
主要成果:
- 观察了冷收缩腔和明显的表面树突微观结构的形成.
- 记录了独特的树突生长在触角和正常方向到滴水表面.
- 描述了微重力中的收缩动态和液体表面流动之间的相互作用.
结论:
- 微重力条件使合金具有新的固化行为,与陆地环境不同.
- 该研究提供了关于在减少对流下合金凝固的基本见解.
- 结果提高了对太空材料加工的理解,并为未来的合金设计提供了信息.
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