【摘要】 采用水浸超声聚焦直入射法对镀锌薄板点焊焊核进行超声C扫描成像检测,分析C扫描图像中各特征部分的超声A扫描信号。超声波C扫描成像方法能够测量点焊焊核直径,检测焊核中常见的几种缺陷如气孔、裂纹以及飞溅,此外采用该方法还能对焊核的外观进行检测。为了获得更为精确的焊核内部结构信息,进一步分析了焊核内部不同形状缺陷的C扫描图像特征及A扫描信号特征,通过这些图像特征和信号特征能够判断焊核内部缺陷的形状及类型。因此,超声C扫描成像法能够在不破坏点焊焊核的前提下全面直观地显示焊核的内外部结构。该方法不仅能够用于评价点焊质量,而且还可以作为辅助手段用于点焊的其他研究中。更多还原

【Abstract】 Ultrasonic C-scan of spot weld on galvanized sheet is carried out by using ultrasonic water immersion focusing method.The A-scan signals of the specific parts of the ultrasonic C-scan image are analyzed.C-scan can be adopted to measure the diameter of the spot weld and discover the inner flaws of the spot weld such as splash,crack,void and inclusion.Besides,C-scan can detect the appearance of the spot weld too.In order to acquire the more accurate information of the inner structure of the spot weld,the characteristic C-scan image and the characteristic A-scan signals which can be used to distinguish the shape and type of inner defects are also obtained.The ultrasonic C-scan image method not only can evaluate the quality of spot weld but also can be a kind of important auxiliary method for spot weld research.更多还原