来自复合材料中不同故障机制的声学辐射的有限元模拟
Manoj Rijal1, David Amoateng-Mensah1, Mannur J Sundaresan1
1Department of Mechanical Engineering, North Carolina A & T State University,1601 E. Market Street, Greensboro, NC 27411, USA.
Materials (Basel, Switzerland)
|January 8, 2025
概括
这项研究模拟了由复合材料层层损坏引起的声辐射信号,使用有限元分析区分纤维断裂,矩阵裂和分层. 这些发现有助于实时监测损坏,以提高结构完整性.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 非破坏性测试 不破坏性测试
背景情况:
- 复合板材表现出由各种因素影响的复杂损伤演变.
- 识别不同的故障模式,如矩阵裂,分层和纤维断裂,对于结构健康监测至关重要.
- 声波发射 (AE) 可以实时量化损害,但区分信号源仍然是一个挑战.
研究的目的:
- 模拟和区分交叉层复合板材中关键故障模式产生的声学发射信号.
- 调查AE信号的特征,对应于矩阵裂,分层和纤维断裂.
- 为了验证使用有限元分析 (FEA) 在建模AE信号生成和传播中进行损害评估.
主要方法:
- 模拟AE信号使用基于增量裂增长的修改步骤冲动.
- 采用线性弹性有限元素分析 (FEA) 来建模Lamb波传播.
- 利用实验减弱数据通过过器来改进模拟的AE波形.
- 专注于使用压电传感器进行表面应变测量.
主要成果:
- 光纤断裂产生了高频 (超过2MHz) 的高阶Lamb波模式.
- 矩阵裂主要产生基本的S0和A0模式,高达650kHz.
- 分层显示出主导的A0模式,频率低于250kHz.
- 信号特性随着源传感器距离的变化而显著变化,需要密集的传感器阵列.
结论:
- 在复合材料中,FEA有效地模拟了来自不同故障模式的AE信号.
- 鲜明的频率信号区分了纤维断裂,矩阵裂和分层.
- 精确模拟AE信号支持实时损坏识别和结构健康监测.
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