在HCP-Ti中将相干双胞胎边界转化为基底镜边界:分子动力学研究
Tao Sun1, Qili Bao2, Yang Gao1
1State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China.
Materials (Basel, Switzerland)
|May 11, 2024
概括
分子动力学模拟揭示了六角密封 (HCP) 合金中的粒度边界如何转变. 一致双边界 (CTBs) 通过脱位排放转变为基底/带边界 (BPBs),影响合金的性能.
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:
- 具有六角密封结构 (HCP) 的 (Ti) 合金表现出复杂的微观结构,具有众多的粒度边界.
- 这些粒度边界,特别是基底/晶格边界 (BPB) 和连贯双边界 (CTB),显著影响合金性能.
- 了解这些边界的机械行为对于HCP Ti合金中的微观结构和性质调节至关重要.
研究的目的:
- 在外部负荷下研究HCP-Ti中基底/镜边界 (BPB) 和连贯双边界 (CTB) 的机械反应.
- 阐明CTB和BPB之间的转换机制.
- 为了解HCP合金中的微观结构和属性调节做出贡献.
主要方法:
- 用分子动力学 (MD) 模拟来研究HCP-Ti.中BPB和CTB的机械行为.
- 模拟专注于这些边界在外部机械应力下的反应.
- 分析涉及跟踪边界转换,失位排放和缺陷积累.
主要成果:
- 一致双边界 (CTBs) 通过双边界步骤的积累和Shockley部分位移的发射,转化为基底/晶格边界 (BPBs).
- 基底/ prismatic 边界 (BPBs) 发出部分位移,并在不匹配向量与Shockley 部分位移 Burgers 向量对齐时,沿堆叠断层生长.
- 由于CTB的近距离导致边界扭曲,促进了部分位移活动,并促进了CTB-BPB的转变.
结论:
- 该研究通过观察到的转化机制解释了CTBs和BPBs在HCP合金中的共存.
- 这些发现提供了关于谷物边界行为如何影响HCP Ti合金的机械性能的见解.
- 这项研究有助于合理设计和控制微结构,以提高合金的性能.
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