基于光源调制的弧形激光超声激发特性及缺陷检测应用  

Excitation characteristics and defect detection application of arc laser ultrasound based on light source modulation

作　　者：李霂维 陈友兴[1] 荀燕琴 曹吉 LI Muwei;CHEN Youxing;XUN Yanqin;CAO Ji(School of Information and Communication Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学信息与通信工程学院,太原030051

出　　处：《无损检测》2025年第3期35-41,共7页Nondestructive Testing

基　　金：国家自然基金联合基金重点支持项目(U23A20636);山西省自然科学基金项目(202103021224189);山西省基础研究计划项目(202303021212208)。

摘　　要：针对激光超声在热弹机制下激发的超声体波信号弱,不易实现工件内部缺陷检测的问题,基于激光光源调制方法,搭建了激光超声检测平台,利用单层金属板从理论和试验两方面分析了弧形激光激励超声体波的传播特性,并以此为基础检测了多层金属板的分层缺陷。试验结果表明,在热弹机制下,相比传统点激光,弧形激光能够激发出更强的体波信号,弧半径对体波激发效率具有显著影响,而激发效率与弧心角呈正相关。此外,弧形激光具备检测微小缺陷的能力,但其检测能力与检测分辨率相互制约。In order to improve the efficiency of bulk wave excitation and defect detection capability in the thermoelastic mode,this paper built a laser ultrasonic detection platform based on the modulation method of laser light source.The propagation characteristics of ultrasonic bulk wave in a single layer of metal plate stimulated by arc laser were analyzed theoretically and experimentally,and the layered defects in multi-layer metal plate were detected on this basis.The experimental results showed that,under the thermoelastic mode,the arc laser was able to excite stronger bulk wave signals compared with the conventional point laser;the arc radius had a significant effect on the bulk wave excitation efficiency,while the excitation efficiency was positively correlated with the arc angle.In addition,the arc laser had the ability to detect small defects,but its detection capability and detection resolution were constrained by each other.

关 键 词：激光超声 热弹机制 弧形激光 

分 类 号：TN249[电子电信—物理电子学] TB551[理学—物理] TG115.28[理学—声学]