基于直接3D数值模拟的实验双轴表面纹模式的分析
Seonho Seok1, HyungDal Park2, Jinseok Kim2
1Center for Nanoscience and Nanotechnology (C2N), Université Paris-Saclay, 91129 Palaiseau, France.
Micromachines
|April 27, 2024
概括
这项研究模拟了符合条件的基板上的薄金属薄膜中的双轴表面纹. 纹模式,如圆柱形或波浪形,取决于双向性比 (BR),使得应用应变的实验估计.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 符合标准的基板上的薄金属薄膜可以在应力下表现出表面纹.
- 之前的研究主要集中在单轴或圆柱形纹模式上.
- 了解双轴纹对于先进的材料应用至关重要.
研究的目的:
- 在符合条件的基板 (苏格兰带) 上,在金薄膜中对双轴表面纹进行直接的3D数值模拟.
- 为了研究双轴负荷对纹模式的影响.
- 建立模拟结果和实验观测结果之间的相关性,以估计应变.
主要方法:
- 使用有限元分析进行直接的3D数值模拟.
- 在合规基板中建模材料的不完美,以启动纹.
- 系统地改变双轴性比率 (BR) 以观察不同的纹模式.
主要成果:
- 纹模式是由双向性比 (BR) 决定的.
- 圆柱形纹在BR<0.5.5时占主导地位.
- 在BR>0.9时出现波纹 (鱼骨) 图案,还观察到棋盘和迷宫模式.
- 模拟结果与实验观察结果非常相匹配,允许应用BR估计.
结论:
- 双轴负荷导致各种纹模式 (圆柱形,波形,棋盘,迷宫),由双轴性比率控制.
- 开发的数值模拟准确地预测了纹行为.
- 这种方法提供了一种可靠的方法,可以根据观察到的纹模式来估计在薄膜中应用的双轴应变.
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