奥氏体不锈钢焊缝超声阵列检测方法  

Nondestructive testing of austenitic welds using method of ultrasonic array

作　　者：杨敬[1,2] 吴斌 焦敬品[1] 王永贤[1] 何存富 YANG Jing;WU Bin;JIAO Jingpin;WANG Yongxian;HE Cunfu(Faculty of Materials and Manufacturing Beijing University of Technology,Beijing,100124,China;Beijing Aerospace Measurement and Control Technology Co.,Ltd.,Beijing,100041,China)

机构地区：[1]北京工业大学,北京100124 [2]北京航天测控技术有限公司,北京100041

出　　处：《焊接学报》2022年第2期1-10,I0002,共11页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(11972053,11772013,12004018)。

摘　　要：在焊接热循环作用下,奥氏体不锈钢焊缝内部呈粗大柱状晶组织,且其取向在焊缝不同区域呈各向异性.针对粗大柱状晶引起的超声波散射和晶粒取向不同导致的声束偏折等问题,进行奥氏体不锈钢焊缝超声阵列检测方法研究.针对超声阵列获得全矩阵数据,发展了一种基于时间反转算子分解的超声阵列信号去噪方法.利用射线追踪法,研究了各向异性介质中超声波传播路径确定方法,并将其应用于奥氏体不锈钢焊缝超声阵列全聚焦成像的声束偏折校正.开展了奥氏体不锈钢焊缝超声阵列检测试验研究.结果表明,基于时间反转算子分解方法可以很好剔除检测信号中的散射噪声,凸显特征回波信息,可将全聚焦成像的信噪比提高10 dB,而波束偏折校正则可以提高超声阵列全聚焦成像中缺陷定位的精度.Under the action of welding thermal cyclic load,the internal peritectic structure of austenitic stainless steel weld is coarse columnar crystal, and its orientation is anisotropic in different areas of the weld. The nondestructive testing of austenitic stainless steel welds is conducted using method of ultrasonic array for the ultrasonic scattering caused by coarse columnar crystals and the sound beam deflection caused by different grain orientations. A signal analysis method based on decomposition of the time-reversal operator is developed for noise reduction processing of ultrasound full matrix data. Using ray tracing method, the ultrasonic wave propagation path determination method in anisotropic media was investigated and applied to the correction of beam deflection for ultrasonic array total focus imaging of austenitic stainless steel welds.Nondestructive testing of austenitic stainless steel welds was conducted using ultrasonic array, and the results showed that the time-reversal operator-based decomposition method was effective for the suppression of scattering noise in the detection signal and highlight the echoes from defects, which can improve the signal-to-noise ratio of full-focus imaging by 10 dB,moreover the beam deflection correction can improve the accuracy of defect localization in total focus imaging of ultrasonic arrays.

关 键 词：时间反转算子分解 奥氏体不锈钢焊缝 射线追踪 全聚焦成像 超声阵列 

分 类 号：TG441.7[金属学及工艺—焊接]