时间反转SH_(0)波跨焊缝检裂纹缺陷研究  

The detection of crack defects by SH_(0) guided wave across weld using time reversal method

作　　者：岳雯溁 周进节[1] 郑阳[2] 张吉堂[1] Yue Wenying;Zhou Jinjie;ZhengYang;Zhang Jitang(School of Mechanical,North University of China,Taiyuan03005l,China;China Special Equipment Inspection and Research Institute,Beijing 100029,China)

机构地区：[1]中北大学机械工程学院,太原030051 [2]中国特种设备检测研究院,北京100029

出　　处：《电子测量技术》2022年第20期167-173,共7页Electronic Measurement Technology

基　　金：国家自然科学基金(62071433)项目资助。

摘　　要：针对水平剪切导波跨越焊缝检测裂纹缺陷信号弱的难题,提出了一种基于SH导波模式的时间反转检方法。本文选择低频的SH_(0)导波模态,建立了3 mm板上跨越焊缝检测缺陷的三维等效模型,并对时间反转检测进行了数值模拟以及实验验证。首先,从模拟角度验证了时间反转可以提高检测焊缝后缺陷的灵敏度。随后,设计和搭建PPM EMAT产生SH_(0)模态波进行常规和时反检测实验。实验验证了时间反转检测的有效性。实验和仿真结果均表明,时间反转法对常规检测中较低的缺陷回波信号有较强的聚焦效果。该方法能够将铝板中的常规信号幅值最大增至3.22倍,可有效检测1 mm的纵向裂纹缺陷。本文为跨焊缝导波检测缺陷提供了新的思路。To solve the problem of weak signal of shear horizontal guided wave detection across weld, a time reversal detection method based on SH guided wave mode is proposed in this paper. The low frequency SH_(0)guided wave mode is selected for this detection. A 3 D equivalent model for the defect detection of cross weld on a 3 mm thick plate was established, and the time reversal detection was simulated numerically and demonstrated by experiment. Firstly, it is verified that time reversal can improve the sensitivity of post-weld defect detection from the perspective of simulation. Then, the PPM EMAT system was designed and built to generate SH_(0)mode wave for conventional and time-reversal detection experiments. Experiments verify the validity of a time reversal detection method. Experimental and simulation results show that the time reversal method has a strong focusing effect on the low defect echo signal in conventional detection. This method can increase the conventional signal amplitude to 3.22 times, and can be used to detect 1 mm longitudinal crack defects effectively. This paper provides a new idea for conducting wave detection of defects across welding seams.

关 键 词：SH导波 时间反转法 跨焊缝 缺陷检测 

分 类 号：TP2[自动化与计算机技术—检测技术与自动化装置]