作者：李茂东¹, 林晓辉², 杨波¹, 洪晓斌²

作者单位：1. 广州特种承压设备检测研究院, 广东 广州 510663;
2. 华南理工大学机械与汽车工程学院, 广东 广州 510640

关键词：分层缺陷;超声导波;小波能量值;防腐层

摘要：

工业用材料表面通常覆盖有非金属防腐层，保证防腐层的完好对实现材料的正常工作具有重要意义。为实现对非金属防腐涂层的分层缺陷检测，该文提出基于小波能量值的分层缺陷损伤评估方法。首先建立超声导波在双层板状介质中的传播模型，提出基于小波能量值的检测理论，制作试样并建立实验平台，分别利用增益值和小波能量值对分层缺陷进行检测比较。实验结果表明随着分层缺陷宽度的增加，达到相同回波幅度的增益值逐渐下降，但增益值方法在较小范围内无法识别出分层缺陷；而接收信号的小波能量值能更好地实现对分层缺陷的检测，特别是在缺陷宽度较低的情况下，采用小波能量法能较好满足分层缺陷的检测需求。基于小波能量值的分层缺陷检测方法可为后续对复杂多层材料检测提供参考。

Detection on delamination damage of nonmetallic erosion resistant coating based on ultrasonic guided waves

LI Maodong¹, LIN Xiaohui², YANG Bo¹, HONG Xiaobin²

1. Guangzhou Research Institute of Special Pressure Equipment Testing, Guangzhou 510663, China;
2. School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China

Abstract: As nonmetallic coating is commonly used on the surface of industrial materials, it is of great importance to ensure that the coating is intact for normal operation of materials. Aiming at detecting the delamination damage of nonmetallic coating on metallic base material, a delamination damage detection method based on wavelet energy is proposed in this paper. Firstly, the propagation model of guided wave in double-layer tubular medium is established and a detection method based on wavelet energy is proposed. Secondly, specimens are made and an experiment platform is built up. Ultimately, the delamination damages are studied and compared using gain value and wavelet energy. Results show that generally, the gain value of the same echo amplitude decreases as the delamination damage grows. However, small damages could not be detected using this method, while the wavelet energy of the detected signals can detect the delaminationdamage more effectively. Especially when the damage is small, wavelet energy method can meet the requirement of detecting the delamination damages. The delamination damage detection method based on wavelet energy can provide a reference for the future studies in the testing of complicated multi-layer materials.

Keywords: delamination damage;ultrasonic guided wave;wavelet energy;erosion resistant coating

2018, 44(6): 22-27  收稿日期: 2018-01-28;收到修改稿日期: 2018-02-22

基金项目: 广东省自然科学基金项目（2014A030313248）；广东省质量技术监督局科技项目（2016CT15）；广州市科技计划项目（201607010171）；佛山市科技计划项目（2016AG100255）

作者简介: 李茂东(1972-),男,辽宁葫芦岛市人,教授级高级工程师,研究方向为承压类特种设备安全检测研究。

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