Infrared thermography nondestructive testing of debond defects in composite materials

To estimate debond defects of glass fiber composite materials applied in the SRM(Solid Rocket Motor), an active infrared thermography nondestructive testing system was set up. The specimen with known debond defects was stimulated by a pulsed heating source and the surface temperature of the specimen was monitored by the infrared camera. According to the difference of the surface temperature, the defects inside the specimen could be detected. The experiment results were compared with the ultrasonic C-scan ones. The results show that the infrared thermography is a fast and effective inspection method for detecting debond defects with the diameter over 10 mm and depth within 5 mm.