铝合金薄板的超声透射法检测

Nondestructive Testing of Al-alloy Thin Plate by Ultrasonic Transmission Method

分析了铝合金薄板内部缺陷以及分层缺陷产生的原因及其分布形态,讨论了常用的金属薄板无损检测方法的优缺点,选择超声透射法对不同厚度的铝合金薄板进行检测。在薄板上制作不同孔径的人工缺陷以模拟分层缺陷,测试在不同人工缺陷区域超声透射信号的幅度变化,并制作了对应的缺陷标定曲线。该方法检测铝合金薄板缺陷时,克服了超声探头的盲区,声束垂直于分层缺陷面,灵敏度高,不易产生漏检。

The defects in Al-alloy thin plate were studied, especially the cause of delamination and its distribution. After discussing the merits and demerits of some nondestructive testing methods about metal thin plate, ultrasonic transmission method was chosen to test Al-alloy plate. Some manual defects which had different diameter were made to simulate delamination defects. The amplitude of transmission signal was processed to plot calibration curve. The delamination defects were easy to distinguish and the testing sensitivity was high because the ultrasonic beam was perpendicular to the defect surface.