在使用声辐射对CFRP复合材料进行准静态内时的损伤定位,识别和进化研究
Jinbo Du1,2, Han Wang1,2, Liang Cheng1,2
1State Key Laboratory of Fluid Power and Mechatronic System, School of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China.
Polymers
|December 23, 2023
概括
本研究引入了一种使用连续波波变换 (CWT) 来检测复合材料损坏的新声辐射方法. 该技术准确地定位了矩阵裂和分层,提高了速度和精度.
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:
- 层状复合材料易受损坏,例如矩阵裂和分层.
- 准确的损坏评估对于结构完整性和安全至关重要.
- 现有的声辐射 (AE) 方法在速度和定位准确性方面存在局限性.
研究的目的:
- 开发和验证一种基于连续波波变换 (CWT) 的新型声辐射 (AE) 方法,用于在层状复合材料中定位和识别损伤.
- 同时识别矩阵裂和分层损伤模式.
- 为了提高基于AE的损坏检测的准确性和减少本地化时间.
主要方法:
- 准静态缩 (QSI) 实验是在层状复合材料上进行的.
- 开发了一个基于连续波波变换 (CWT) 的损害定位算法,利用特定AE信号频段的到达时间差异.
- 通过分析CWT的最大频段,特别是40kHz-50kHz范围内,确定了损坏模式 (矩阵裂和分层).
主要成果:
- 与现有技术相比,拟议的基于CWT的方法显著降低了与现有技术相比的平均位置误差,从3.81%降至2.31%.
- 平均信号定位时间从几分钟大幅缩短到2秒.
- 矩阵裂和分层显示在40 kHz-50 kHz频段内有明显的特征,矩阵裂之前的分层.
- 非线性机械反应与增加的矩阵裂纹相关,并且微观分层之前进行了宏观分层.
结论:
- 基于CWT的AE技术提供了一个高度准确和高效的方法,用于定位和识别复合材料中的矩阵裂和分层.
- 该方法提供了实时损害监测功能,对于预测灾难性故障至关重要.
- 了解损伤演变的序列和特征 (矩阵裂随后分层) 可以增强复合结构的预测模型.
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