Backscattered Transverse Wave Imaging of Cracked-Faces with Linear and Nonlinear Ultrasonics
Backscattered Transverse Wave Imaging of Cracked-Faces with Linear and Nonlinear Ultrasonics
复制标题
利用线性和非线性超声波对裂纹面进行后向散射横波成像
DOI：
10.2320/matertrans.i-mra2007847
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发表时间：
2007
影响因子：
1.2
通讯作者：
T. Ito
中科院分区：
文献类型：
--
作者：
K. Kawashima;M. Murase;Keiji Shibata;T. Ito
提出了一种新的裂纹表面本身的后向散射波成像方法。与传统的TOFD和相控阵技术不同，该技术可以捕获分散在崎岖的疲劳裂纹面和/或晶间应力腐蚀裂纹（SCC）面上的波。通过使用点聚焦换能器和扫描仪将超声波光束聚焦到这些面部的每个峰值上，并将散射波振幅映射到扫描平面上，我们就能得到裂纹面部本身的图像。对于nm开口的紧密裂纹面，用有限振幅的爆发波拍击和/或摩擦这种面所产生的二次谐波幅值和更高次谐波幅值以类似的方式映射。通过对比裂纹面的线性和非线性图像，可以对裂纹的张开程度进行分类。给出了疲劳裂纹表面的一些图像。
A new backscattered-wave imaging of a cracked-face itself is proposed. Different from the conventional TOFD and phased array techniques, the wave scattered on a rugged fatigue-cracked face and/or intergranular stress-corrosion-cracking, SCC, face is captured in this technique. By focusing ultrasonic beams at every peak on those faces with a point-focused transducer and a scanner and by mapping the scattered-wave amplitudes on the scanned plane, we make an image of the cracked face itself. For tight cracked faces of nm opening, the second and higher harmonic amplitudes, generated by clapping and/or rubbing such a face with finite amplitude burst waves, are mapped in the similar way. By comparing the linear and nonlinear images of cracked faces, we can classify the extent of the crack opening. Some images of fatigue cracked faces are shown.