Accuracy assessment of ultrasonic C-scan and X-ray radiography methods for impact damage detection in glass fiber reinforced polyester composites

The present study introduces two quantitative parameters to compare the accuracy of ultrasonic C-scan testing and X-ray radiography methods in the damaged area detection under low-velocity impact in polymer-based composites. For this purpose, the hand lay-up technique of composite processing was employed to prepare the composite specimen. A composite specimen consisting of the glass fiber reinforced with the unsaturated polyester resin was considered for this investigation. The impact tests at different energy levels were carried out to create three damaged areas in this composite specimen. Because the glass/polyester specimen had a transparent surface, a digital scanner was used to obtain an ideal image of specimen representing the region and edge of the impacted areas. Two image quality factors were introduced as quantitative parameters to compare the ultrasonic C-scan and X-ray radiography results with those of an ideal image. The results of this study showed that the ultrasonic C-scan is a more accurate method for inspection of the GFRP specimen.