格子不合适对失位处降水的影响:相场晶体模拟
Hong Mao1,2, Changlin Zeng1, Zhikang Zhang1
1Hunan Institute of Science and Technology, College of Mechanical Engineering, Yueyang 414006, China.
模拟显示,合金中的格子不合适显著增加了沉核,导致更多的,较小的沉物. 这影响了沉形态和脱位运动,指导了高强度合金的设计.
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.
- 计算材料科学科学 计算材料科学
背景情况:
- 超和合金对于高强度应用至关重要.
- 了解老化过程中的沉物形成是优化合金性能的关键.
- 格子不合适是影响降水动力学和形态学的关键因素.
研究的目的:
- 通过原子尺度模拟,研究格子不合适对合金中沉物形成的影响.
- 阐明格子不合适,核化速率,沉物大小和形态学之间的关系.
- 探索格子不合适如何影响脱位移动性及其对合金强度的影响.
主要方法:
- 用原子尺度的模拟来建模沉物核和生长.
- 不同的格子不合适值在模拟中被系统地变化.
- 该研究分析了核化速率,沉物大小和形态,以及脱位相互作用.
主要成果:
- 增加的格子不合适显著增加了沉物核化速率.
- 较高的格子不合适导致沉物数量更多,尺寸更小.
- 沉形态取决于格子不合适的程度.
- 在更高的格子不合时,第二阶段的早期核化抑制了脱位运动.
结论:
- 格子不合适是沉核形成的主要驱动因素,并影响沉特性.
- 这些发现为设计先进的高强度合金提供了理论基础.
- 控制格子不合适提供了一条定制合金微观结构和机械性能的途径.
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