LIU Hongwei, WU Xuhui, HUANG Ziyang, WANG Xingguo, LI Xiaogao, FAN Yuenong, LIU Yang

(School of Mechanical and Electronic Engineering, Jingdezhen Ceramic University, Jingdezhen 333403, Jiangxi, China)

Abstract: In order to accurately measure the thickness of ceramic coating by using non-destructive method, propagation characteristics of ultrasonic guided wave in double layer medium were analyzed, based on the wave equation and global matrix method. The dispersion equation of ideal bonded ceramic coating interface was derived. The dispersion curves of ceramic coatings with different thicknesses were obtained by numerically solving the dispersion equation. According to the dispersion curves, the increase in ceramic coating thickness would make the dispersion curve to shift to the left, while the S0 mode shifted to the left in a certain range. Experimental simulation was carried out by using the software Comsol MultiPhysic. The acoustic propagation times for the coatings with different thicknesses were basically consistent with the numerical results. Our method could be used as a theoretical basis for the measurement of thickness of ceramic coatings with ultrasonic guided wave detection.

Key words: ultrasonic guided wave; ceramic coating; dispersion curve; phase velocity