焊缝散射条件下板中超声导波直线阵列多帧变秩成像检测  

Variable-rank imaging and testing of multi-frames for line array of ultrasonic guided waves with weld scattering

作　　者：朱新杰 李永涛 邓明晰 姚森 张洁 ZHU Xinjie;LI Yongtao;DENG Mingxi;YAO Sen;ZHANG Jie(School of Materials Science and Engineering,North Minzu University,Yinchuan,750021,China;College of Mechatronic Engineering,North Minzu University,Yinchuan,750021,China;College of Aerospace Engineering,Chongqing University,Chongqing,400044,China)

机构地区：[1]北方民族大学,材料科学与工程学院,银川750021 [2]北方民族大学,机电工程学院,银川750021 [3]重庆大学,航空航天学院,重庆400044

出　　处：《焊接学报》2025年第1期80-86,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(12164001,12134002);宁夏回族自治区重点研发计划项目(引才专项)(2021BEB04006);宁夏回族自治区复合制造系统工程技术研究中心资助项目(2023GCJS008)。

摘　　要：焊缝散射条件下板中超声导波阵列成像检测具有重要意义.将超声水平剪切(shear horizontal,SH)导波直线阵列多帧变秩成像用于焊接板结构检测,探讨了在焊缝散射条件下超声导波直线阵列多帧变秩成像机理,分析了接收矩阵与其秩的关系.结果表明,当焊缝散射因子k≥2时,接收矩阵的秩会增加至合成孔径阵列阵元数的(k-1)倍.随着接收矩阵秩的增加,多帧变秩图像缺陷灰度和信噪比(signal-to-noise ratio,SNR)得到不同程度增大,半满秩时SNR曲线出现拐点,秩为满秩的2/3时,成像效果较好.超声导波直线阵列多帧变秩成像能够有效表征焊接结构板中与波长尺寸相当的缺陷信息,成像检测试验验证了理论分析的有效性,焊缝散射条件下板中超声导波直线阵列多帧变秩成像检测具有较好的可行性.The imaging and testing of ultrasonic guided wave array in plates under the condition of weld scattering is of great significance.The variable-rank imaging of multi-frames for line arrays of ultrasonic shear horizontal(SH)guided waves is proposed for testing of weld plate.The imaging mechanism of variable-rank imaging of multi-frames for line array of ultrasonic guided waves with weld scattering is discussed,and the relationship between the receiving matrix and its rank is analyzed.The results show that when the weld scattering factor k≥2,the rank of the receiving matrix will increase to(k-1)times the number of elements in the synthetic aperture array.With the increase of the rank of the receiving matrix,the defect grayscale and signal-to-noise ratio(SNR)of the variable-rank images of multi-frames increase to varying degrees.The SNR curves would have inflection points when the rank is half of the full rank,and the imaging effect would be better when the rank is two-thirds of the full rank.The variable-rank imaging of multi-frames for line array of ultrasonic guided waves would effectively characterize the defects with the same wavelength size in the weld plate.The imaging and testing of experiment verifies the effectiveness of the theoretical analysis,which demonstrate the feasibility and validity of this research approach.

关 键 词：焊缝散射 超声导波 直线阵列 多帧变秩 成像检测 

分 类 号：TG439.9[金属学及工艺—焊接]