Research on ultrasonic guided wave structural damage identification method based on time-delay cumulative imaging algorithm

In this paper, the finite element analysis method is used to simulate the dynamic propagation process of Lamb waves in the aluminum alloy plate, and the modulation effect of damage on the received signal is analyzed. By analyzing the dispersion curve of Lamb waves propagating in the aluminum alloy plate, a narrow-band Hanning window modulated sine wave with the center frequency of 150 KHz and the period of 5 is selected as exciting signal, based on the delay-and-sum imaging algorithm, using a honeycomb sensor array composed of six piezoelectric sensors, the simulated damage of additional heavy weight in aluminum alloy plate with size of 600mm 600mm 2mm was identified. The positioning errors of the three experiments were 8.06 mm, 13.34 mm and 14 mm. The experimental results show that the delay-and-sum imaging algorithm can accurately locate the damage in the aluminum alloy plate.