Effects of Vibration Displacement on the Detection Sensitivity of Lamb Waves

To research the relationship between the sensitivity of Lamb modes and the vibration displacement, the artificial delamination defects were made in steel sheet and tested nondestructively by Lamb waves in pulse-echo method. The time domain signals, obtained from the defect-free plate and the defected ones, respectively, were analyzed by time-frequency analysis, the result showed there was a good corresponding relationship between the sensitivity of Lamb modes and the vibration displacement.