金属中的塑性变形的几何形状,以零件式的异面变换为单位
Yan Beygelzimer1, Alexander Filippov2, Dmytro Orlov3
1Donetsk Institute for Physics and Engineering Named After O.O. Galkin, NASU, Kyiv, Ukraine.
Scientific reports
|August 18, 2024
概括
本研究介绍了逐块的同位变换 (PWIT) 来描述晶体固体变形,提供了一个超越脱位理论的新几何框架. 这种方法为严重的塑性变形中的现象提供了新的假设,例如固态流和机械辅助扩散.
科学领域:
- 材料科学 材料科学 材料科学
- 固体力学 固体力学是什么
- 晶体学 晶体学是指结晶学.
背景情况:
- 两个多世纪以来,人们一直在研究晶体固体的变形机制.
- 脱位理论占主导地位,但具有局限性,需要新的概念来完整描述.
- 现有的模型难以量化地描述晶体变形中的物理现象.
研究的目的:
- 提出一个连贯的对晶体固体运动和变形的几何描述.
- 作为一个新的框架,引入逐块同位变换 (PWIT).
- 为在严重的塑性变形中观察到的现象开发新的假设.
主要方法:
- 描述晶体变形使用断片异面变换 (PWIT).
- PWIT涉及转换,旋转和镜像反射,保持原子间距离.
- 分析PWIT中的不连续性,以解释脱位,脱位和双胞胎.
主要成果:
- 建立了塑性变形的概念框架,因为PWIT是建立的.
- 提出了关于高压扭转中的"固态流"的新假设.
- 在简单剪切变形中提出了机械辅助扩散的新假设.
结论:
- PWIT提供了一种统一的几何方法来处理晶体变形.
- 这种框架可以提高物理现象的描述,并有助于开发预测模型.
- 该PWIT概念为严重的塑性变形行为提供了新的见解.
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