Automated Laser Ultrasonic NDT of Carbon Fibre Reinforced Polymer Parts

Publication, 2020


M. Gärtner , B. Reitinger, W. Haderer, B. Plank, J. Kastner, J. Gruber, G. Mayr, J. Vicki, P. Burgholzer, E. Scherleitner - Automated Laser Ultrasonic NDT of Carbon Fibre Reinforced Polymer Parts - 12th International Symposium on NDT in Aerospace (2020), Williamsburg, Virgina, United States of America, 2020, pp. 10


We present the application and the results of laser ultrasonic scanning systems on fibre-based composites and the current state of development of this method at RECENDT. First we benchmark this technique with X-ray tomography and infrared thermography and then show a robotized scanning system dedicated for the aerospace industry. The laser ultrasonic systems use a 532 nm Nd:YAG pulsed laser for excitation and a 1064 nm two-wave-mixing interferometer for detection. The fibre coupling enables a flexible scan head for the automation of the system. The laser ultrasonic technique is demonstrated on a sample with artificial defects, such as PTFE-foils as a delamination source. The results are compared with reference NDT-methods such as X-ray computed tomography and active thermography, and the individual advantages and disadvantages are discussed. Further, a robotised scanning system will be presented, which has been developed under the H2020 Clean Sky 2 project ACCURATe. The sampling rate of this system is 400 Hz, which enables large parts to be inspected at the required speed. A large aircraft part made of carbon fibre reinforced polymer was manufactured and investigated for real world defect measurements.