形成不混合的合金粉末,具有卵型微观结构
1Department of Materials Science, Graduate School of Engineering, Tohoku University, Aoba-yama 02, Sendai 980-8579, Japan.
概括
研究人员在重力作用下的铜铁合金中创建了一个卵型核心微结构. 这一发现由马兰戈尼运动解释,证明了微观结构.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 物理化学 物理化学
背景情况:
- 蛋型核心微观结构,其中一个合金被另一个合金包围,以前已经观察到.
- 这种微观结构通常是在太空实验期间形成的.
研究的目的:
- 研究在地面重力条件下的铜铁基合金中形成卵型核心微结构的可能性.
- 了解形成这种独特的微观结构的潜在机制.
主要方法:
- 使用传统的气体原子化技术制备铜铁基合金.
- 在标准重力下分析得到的粉末形态和微观结构.
主要成果:
- 在重力下的铜铁合金中成功获得了卵型核心微观结构.
- 观察到小液相始终形成核心,偶尔会形成外.
- 确定了由温度依赖的界面能量驱动的马兰戈尼运动作为形成机制.
结论:
- 蛋型核心微结构可以在没有微重力条件的铜铁合金中形成.
- 马兰戈尼对流是形成这种微观结构的关键因素,即使在高冷却速度下也是如此.
- 这项研究扩大了对合金固化和微观结构发展的理解.
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