中国激光, 2014, 41 (5): 0508004, 网络出版: 2014-04-16
基于Hilbert变换的激光超声波成像技术在缺陷检测中的应用
Application Laser Ultrasound Imaging Technology for Detecting Defect Based on Hilbert Transform
激光技术 Hilbert变换 激光超声波 脉冲激光器 表面缺陷 定量检测 laser technique Hilbert transform laser ultrasonic pulsed laser surface-breaking defects quantitative detection
摘要
介绍了一种基于Hilbert变换的激光超声波传播图像方法,通过采用脉冲激光器在被测材料表面产生超声波信号,对接收的超声波信号进行Hilbert 变换,并详细分析了超声波信号在被检测材料表面传播的时域波形图,最后利用超声波成像技术将超声波信号在被测材料的传播过程进行图像显示。实验结果表明:采取Hilbert对超声波信号进行变换的方法不仅能有效地提取超声波信号在缺陷处传播的信息,还能从超声波传播的图像中直观、高效地检测出表面缺陷的形状、大小及分布情况。因此,提出的Hilbert变换的激光超声波成像技术为工业中缺陷的定量检测提供了方法。
Abstract
This paper describes a method of laser ultrasonic propagation imaging based on Hilbert transform. The ultrasonic signals are excited by pulsed laser on the measured material surface. Then ultrasonic signal is transformed by Hilbert transfrom. and time-domain waveforms of analyzed measured ultrasonic signal propagation. Finally, ultrasonic signal propagation in the material is displayed by ultrasound imaging technology. The experimental results show that taking the ultrasonic signal Hilbert transform method can not only effectively extract the ultrasonic signal propagation at the defect, but also the shape, size and distribution of surface defects can be intuitive, efficiently detected by ultrasonic propagation imaging. Hence, the Hilbert-transform ultrasonic propagation imaging technology provides a method for quantitative detection of defects in manufacturing.
曾伟, 王海涛, 田贵云, 方凌, 汪文. 基于Hilbert变换的激光超声波成像技术在缺陷检测中的应用[J]. 中国激光, 2014, 41(5): 0508004. Zeng Wei, Wang Haitao, Tian Guiyun, Fang Lin, Wang Wen. Application Laser Ultrasound Imaging Technology for Detecting Defect Based on Hilbert Transform[J]. Chinese Journal of Lasers, 2014, 41(5): 0508004.