Objective For quality inspection of brazed joints in aluminum alloy honeycomb panels, applying destructive testing methods may result in low inspection efficiency and serious material waste. In contrast, ultrasonic testing is a non-destructive testing method with high inspection efficiency. Therefore, it is necessary to conduct research on ultrasonic quantitative inspection of brazed joints in aluminum alloy honeycomb panels.

Method The principles of ultrasonic testing and the testing equipment are introduced. The internal forming quality of brazed joints in aluminum alloy honeycomb panels is identified through ultrasonic echo signals, and the joint connection state is analyzed using ultrasonic A-scan signals. An ultrasonic C-scan image is generated using the maximum amplitude of the first ultrasonic echo, it highlighted the edge regions of the brazed joints in aluminum alloy honeycomb panels. Based on the ultrasonic C-scan images, the boundaries of the brazed joints are extracted using image processing methods, and the cumulative area of the brazed joint region is calculated using the equivalent trapezoidal method. Twelve defect-free standard specimens and twelve defective standard specimens are grouped respectively, and the detection results of the two groups are subjected to validation analysis.

Result & Conclusion  The validation results show that the ultrasonic measurement values of the two groups of specimens welding are in good agreement with the metallographic measured values. For the measured and actual bonded values of the two groups of specimens, the mean differences are 0.075 0 mm and 0.002 5 mm, respectively, and the corresponding standard deviations are 0.13 mm and 0.14 mm.