在压缩负载下的薄膜多层柱子中的剪切带形成:机械学研究
Yu-Lin Shen1, Kasandra Escarcega Herrera1
1Department of Mechanical Engineering, University of New Mexico, Albuquerque, NM 87131, USA.
Materials (Basel, Switzerland)
|September 13, 2025
概括
微柱压缩揭示了分层材料中的剪切带形成. 计算模型证实了应变局部化和材料行为影响这些故障模式.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 微柱式压缩是分析纳米和微层材料的关键技术.
- 实验研究经常观察到塑料的不稳定性,特别是剪切带,导致故障.
- 了解剪带形成对于预测材料性能至关重要.
研究的目的:
- 从连续力学角度计算调查微柱压缩中剪带形成的共同性.
- 为了将数值发现与变形和损伤的实验观测相关联.
- 探索影响剪切带发展的因素.
主要方法:
- 对柱状薄膜复合材料进行了系统的有限元素分析 (FEA).
- 该研究的重点是模拟压力应变应变反应和应变场演变.
- 使用数值模型可视化剪切偏移,并与实验显微镜进行比较.
主要成果:
- 一旦塑料产量开始,FEA 证明了菌株局部化.
- 数字模型成功地复制了实验中观察到的明显的剪切偏移.
- 材料构成性行为 (应变硬化/软化) 和几何缺陷显著影响了剪带形成.
结论:
- 剪切带的形成是塑料在微柱压缩中产生的固有结果,可以通过连续模型预测.
- 材料特性和几何细节决定了剪切带的形态和发生.
- 计算方法提供了对层板故障背后的机制有价值的见解.
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