基于超声检测的镁合金棒材缺陷识别及定位

Defects Recognition and Positioning of Mg Alloy Bars Based on the Ultrasonic Detecting

针对镁合金棒材的近中心缺陷和近表面缺陷,分别采用探头垂直入射或偏心入射的超声检测方式,然后运用滤波去噪等信号处理方法对原始信号及特征回波信号进行特征提取,寻找特征信号规则,进而判定缺陷类型,如孔状缺陷、裂纹状缺陷等。利用小波变换原理增强原始信号,使B扫描成像图清晰易辨别,最终根据棒材和B扫描图比例关系,计算出缺陷位置。为合金类构件的缺陷检测提供了一种有效的简单快捷的检测手段。

In order to accurately detect the defects, such as near-center or near-surface defects, in the magnesium alloy bars, ultrasonic inspection with vertical or eccentric incidence was applied. Through filtering the original signal denoising method and extracting characteristics of echo signal feature, a signal was found to recognize the defect types, such as pore, crack defects. Based on wavelet transformation enhancing original signal, B-scan image becomes clear and easy to be identified. Furthermore, according to the bars and B-scan image ratio relation, defect locations were calculated. The technology provided a simply and rapidly effective way for detecting defects in the alloy structural components.