文献类型：期刊文献

英文题名：Non-contact phase coded excitation of ultrasonic Lamb wave for blind hole inspection

作者：Tang, Jianying[1];Zhu, Wujun[1];Qiu, Xunlin[1];Song, Ailing[1];Xiang, Yanxun[1];Xuan, Fu-Zhen[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety MOE, Shanghai 200237, Peoples R China

年份：2022

卷号：119

外文期刊名：ULTRASONICS

收录：;EI(收录号：20214111006749);WOS:【SCI-EXPANDED(收录号:WOS:000708992900003)】；

基金：This work was supported by the National Natural Science Foundation of China [12025403, U1930202, 51835003] .

语种：英文

外文关键词：Air-coupled ultrasonic testing; Lamb wave; Simulation; Phase coded excitation; Modified RAPID

摘要：The combination of air-coupled ultrasonic testing (ACUT) and ultrasonic Lamb wave is featured with longdistance propagation and high sensitivity to discontinuities, which is a promising method for rapid and accurate inspection of plate-like materials and lightweighted structures. However, dispersive nature of Lamb wave, signal attenuation plus inevitable noises would lead to low signal-to-noise ratio (SNR). To address this problem, phase coded excitation and pulse compression technique are proposed in this paper to achieve higher SNR by over 10 dB in received signals. 13-bit and 1-carrier-period Barker code is employed as both main lobe peak and Peak Side-lobe Level (PSL) are relatively high. It is demonstrated that A0 mode Lamb wave has good localization ability for defects based on these SNR-enhanced signals. Furthermore, Damage Index (DI) and modified Reconstruction Algorithm for the Probabilistic Inspection of Damage (RAPID) are applied to realize ultrasonic imaging based defect evaluation. Results show that the imaging results agree well with the actual artificial defects in terms of size and shape. Lamb-wave-based air-coupled ultrasonic testing, combined with DI and ultrasonic imaging algorithm, could be a potential way in the NDT of lightweighted structures.