Mode Identification and Application for Nondestructive Evaluation of Thin Aluminum Sheet by Lamb Waves

The holes with different diameters were made in thin aluminum sheet with thickness of 0.7 mm to simulate the hole-class defects. Frequency dispersion curves and particle displacement curves were drawn by software Matlab. Based on frequency dispersion curves and particle displacement curves, S0 mode wave was selected out. Experimental results showed that good corresponding relationship between amplitude of S0 mode wave and size of the given defect existed.