Digital Imaging Detection of Aluminum-honeycomb Sandwich Structure

The typical defects of honeycomb sandwich structure are debonding between the skin and the honeycomb core, deformation of honeycomb core, cracking of honeycomb core, water accumulation in honeycomb and so on, yet a single non-destructive testing method can not effectively solve the defect detection problems of honeycomb sandwich structure. Firstly, six kinds of typical artificial defects are manufactured for aluminum honeycomb sandwich structure. Secondly, inclusion, honeycomb core deformation, honeycomb core fracture, rich glue and other volumetric type defects were detected using digital X-ray imaging of digital radiography and computed radiography, the digital image of defects are acquired and image quality is well, and the contrast analysis were carried out. Thirdly, digital X-ray imaging of digital radiography was used to detect the water accumulation in honeycomb, the amount of water will affect the image gray. Lastly, aiming at the aluminum honeycomb sandwich structure which contains artificial debonding defect, the bonding quality of honeycomb sandwich structure was detected by ultrasonic pulse reflection method of C-scan imaging, ultrasonic C-scan digital imaging of debonding defect was obtained by amplitude imaging of bottom wave. The results show that: the combination of digital X-ray imaging and ultrasonic C-scan imaging will provide a digital non-destructive testing method for honeycomb sandwich structure.