摘要
兰姆波在板材的缺陷检测中具有重要的地位,但兰姆波在裂纹检测过程的可视化实验研究较少。通过激光超声可视化技术,观察了激光激励出的宽频兰姆波在0.4 mm深、0.2 mm宽的裂纹上的反射和透射现象;并利用带通滤波技术,研究了不同中心频率的兰姆波在裂纹上的散射特性。结果发现:兰姆波在裂纹上发生了模态转换现象,出现了传播速度较快的兰姆波模态;并随着兰姆波频率的增加,反射兰姆波的能量增强。该研究为板中裂纹的兰姆波检测提供了实验参考。
Lamb wave plays a significant role in plate defect testing,but the visualized research on Lamb wave scattering at cracks is still not enough.In this paper,the laser-ultrasonic visualization inspection method is used to inspect the reflection and transmission of the laser excited broadband Lamb wave at a crack of 0.4 mm deep and 0.2 mm wide.In addition,the scattering characteristics of Lamb wave with different center frequencies at cracks are studied by band-pass filtering technique.It is found that the mode transformation of Lamb wave occurs at cracks and a mode with faster velocity is found.As the frequency increases,the reflected Lamb wave is getting more energy.This research offers an experimental reference for the crack detection of Lamb wave.
作者
李阳
杨连杰
孙俊杰
路培鑫
邹云
LI Yang;YANG Lianjie;SUN Junjie;LU Peixin;ZOU Yun(School of Mechanical and Power Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China;Henan Province Engineering Laboratory for Anti-Fatigue Manufacturing Technology,Zhengzhou 450001,Henan,China)
出处
《声学技术》
CSCD
北大核心
2020年第2期157-160,共4页
Technical Acoustics
基金
国家自然科学基金(51705470)
河南省重点研发与推广专项(18A460032)
河南省高等学校重点科研项目(18A460032)。
关键词
检测
激光超声
可视化
兰姆波
散射
testing
laser ultrasonic
visualization
Lamb waves
scattering
