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Updated: Jan 18, 2026

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Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
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对于FCC金属:Ag和Ni的微结构稳定性和过渡到不稳定的摩擦:
Alexey Moshkovich1, Inna Popov2, Sergei Remennik2
1Department of Science, Holon Institute of Technology, Holon 5810201, Israel.
Materials (Basel, Switzerland)
|September 13, 2025
概括
在Ag和Ni中的摩擦涉及复杂的脱位动态,导致微观结构变化和独特的故障模式. 了解这些过程是预测在tribological压力下的材料行为的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 部落学 (tribology) 是一个学科.
- 纳米机械学 纳米机械学
背景情况:
- 摩擦显著影响材料的微观结构,影响机械性能.
- 脱位堆积在塑性变形和在tribological压力下失败中至关重要.
- 纳米晶体FCC金属对摩擦引起的应力表现出独特的反应.
研究的目的:
- 分析在Ag和Ni摩擦期间的脱位生成和消灭机制.
- 在平稳状态和不稳定的摩擦过程中研究微观结构的稳定性和不稳定性.
- 为纳米晶体金属在摩擦下塑性变形和故障提出理论模型.
主要方法:
- 微观结构演化的分析,包括双胞胎束,剪切带和动态再结晶.
- 开发用于纳米晶体FCC金属的脱位动态的理论模型.
- 引入相似系数 (K) 来比较跨尺度的塑料变形.
主要成果:
- Ag摩擦导致孔隙形成,接触面积减少,剪切应力增加.
- 尼的摩擦导致了易碎的骨折和灾难性的故障,通过氧化的形成.
- 考虑了微结构稳定性,强度-柔性权衡和纳米结构稳定性的模型.
结论:
- 摩擦下的脱位动态决定了特定材料的损伤和故障机制.
- 理论模型提供了对塑料变形,故障和纳米结构稳定性的见解.
- 了解尺度依赖变形对于预测材料性能至关重要.
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