基于一致对应力理论的微/纳米板中的Lamb波的模态位移分析
Hai Huang1, Wei Guan2, Xiao He3
1Department of Astronautics and Mechanics, Harbin Institute of Technology, Harbin 150001, China; State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
Ultrasonics
|February 21, 2024
概括
尺度效应显著改变了微观结构中的引导波传播. 这项研究使用一致的对应力理论来分析微板中的模态位移,这对于Lamb波非破坏性测试至关重要.
科学领域:
- 固体力学 固体力学是什么
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 由于尺度效应,连续力学理论不足以描述微尺度结构中的波传播.
- 了解微/纳米尺度板块中的模态位移对于基于Lamb波的非破坏性测试 (NDT) 至关重要.
研究的目的:
- 使用一致对应力理论研究同位素微/纳米尺度板块中的模态位移.
- 评估尺度效应对无线探测技术应用中的引导波传播的影响.
主要方法:
- 采用一致对应力理论来解释波传播中的规模效应.
- 使用数学推导与单数值分解.
- 通过应用正常应力源来计算激发幅度,以确定内平面和外平面位移.
主要成果:
- 发现当相位速度与剪切波速度相匹配时,在反对称模式下,平面内位移在板面上消失.
- 通过交叉对称和反对称的分散曲线来确定在自由表面上消失的特定频率.
- 在微观和宏观结构之间表现出明显的模式移位特征.
结论:
- 一致的对应力理论有效地捕捉了影响微观结构中引导波传播的规模效应.
- 这些发现为微观结构的超声波非破坏性测试提供了理论见解,特别是关于Lamb波NDT中模式选择.
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