如何停止谷物生长:纯材料中谷物生长停滞的机制
Elizabeth A Holm1, Stephen M Foiles
1Computational Materials Science and Engineering Department, Sandia National Laboratories, Albuquerque, NM 87185-1411, USA. eaholm@sandia.gov
概括
在晶体材料中,颗粒的生长因颗粒边界的热粗而停止,而不仅仅是溶液阻力. 这一发现甚至适用于高纯度材料,为多晶微结构提供了新的视角.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 多晶材料很少达到单晶平衡状态,这是由于粒度的增长停止.
- 谷物生长停滞通常归因于溶液阻力,但它也发生在高纯度材料中.
研究的目的:
- 研究高纯度多晶材料中谷物生长停滞背后的机制.
- 探索谷物边界热粗在停止谷物生长中的作用.
主要方法:
- 利用了中等尺度的谷物生长模型.
- 经过大规模多晶分子动力学模拟的验证模型.
- 分析了光滑 (缓慢) 与粗 (快速) 粒度边界的影响.
主要成果:
- 鉴定了热粗作为谷物边界流动性突然变化的原因.
- 证明,即使是缓慢移动的边界的小部分也可以有效地阻止谷物生长.
- 观察到,在典型的回火温度下,多晶体包含了光滑和粗的边界.
结论:
- 谷物边界粗化为谷物生长停滞提供了一个替代机制.
- 这种机制适用于高纯度的材料,独立于溶液阻力.
- 了解边界粗对于控制多晶微结构至关重要.
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