Hybrid laser and air-coupled ultrasonic defect detection of aluminium and CFRP plates by means of Lamb mode

Abstract

This study presents two non-contact systems – hybrid laser with air-coupled ultrasound and pure air-coupled ultrasonic system for the non-destructive inspection and detection of flaws in CFRP and aluminium plates. B-scans are used to identify the size and location of the defects. The defects are detected through changes in amplitude of the waves passing through them. B-scans, represented as intensity graphs, clearly show the changes in the defect profiles. In addition, there is agreement between the experimental values of the diameter of the defect and the measured values. The two systems and configurations are tested and compared in order to determine their effectiveness in defect identification. The results of this study prove the potential of these non-destructive and non-contact systems for defect detection in aluminium and CFRP composites.

Keywords

• Non-destructive testing
• Laser ultrasound
• Air-coupled transducer
• Defect detection
• Lamb mode
• Aluminium