Acoustic excitated laser shearography testing of aerospace foam materials

The principle of laser shearography with acoustic excitation was presented in this paper. For the 30 mm thickness sprayed on foam insulation test panel, using phase-reversal time-averaged shearography with acoustic excitation was used the multiple-frequency sweep ranging from 1 kHz to 4 kHz, following that a 30 mm square defect was detected. Combined with practical experience, experimental results show that laser shearography is a effective NDT method, suiting for debond defects detection in sprayed on foam insulation.