采用自行研制的超声换能器和透声楔块,对99mm厚奥氏体焊缝进行了超声扫描成像检测.为消除透声楔块中超声的散射噪声,将检测信号与楔块中的信号进行了相消处理.利用基于匹配追踪和小波分析的信号处理方法,有效消除了焊缝中粗大晶粒造成的材料噪声信号,提高了厚壁焊缝超声检测的信噪比.基于经过信号预处理的超声扫描信号,生成了焊缝的超声扫描图像,并对图像分辨率、缺陷定位精度进行了分析.结果表明:该方法可检测到焊缝试块中φ2人工横孔,实现了奥氏体厚壁焊缝缺陷的超声检测成像.
参考文献
| [1] | 栗卓新,李国栋,魏琪,蒋建敏.不锈钢焊接冶金的研究进展[J].中国机械工程,2005(02):184-187. |
| [2] | 袁涛,曹怀祥,祝卫国,王春茂.TOFD超声成像检测技术在压力容器检验中的应用[J].压力容器,2008(02):58-60,22. |
| [3] | 高双胜,刚铁,王军,郭小罗.电子束焊缝超声无损检测声场特性及回波特征[J].焊接学报,2006(02):93-96. |
| [4] | 刘松平,刘菲菲,张丙法,王瑞川,李乐刚,关洪光.管道焊缝超声多维成像检测技术[J].无损检测,2008(02):77-80. |
| [5] | A. Badidi Bouda;S. Lebaili;A. Benchaala .Grain size influence on ultrasonic velocities and attenuation[J].NDT & E international: Independent nondestructive testing and evaluation,2003(1):1-5. |
| [6] | CHASSIGNOLJE B;VILLARD D;NGUYEN VAN CHI G.Ultrasonic propagation in austenitic stainless steel welds-approximate model and numerical methods results and comparison with experiments[A].New York:American Institute of Physics,2000:153-160. |
| [7] | Brown L.F.;Mason J.L. .Disposable PVDF ultrasonic transducers for nondestructive testing applications[J].IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,1996(4):560-568. |
| [8] | 郑中兴.大厚度奥氏体钢焊缝超声检测用纵波斜射双晶探头研制[J].北方交通大学学报,1999(03):115-119. |
| [9] | MALIK M A;SANJIE J.Gabor transform with optimal time-frequency resolution for ultrasonic applications[A].Piscataway:IEEE Ultrasonics,Ferroelectronics and Frequency Control Society,1998:817-820. |
| [10] | R. Drai;F. Sellidj;M. Khelil;A. Benchaala .Elaboration of some signal processing algorithms in ultrasonic techniques: application to materials NDT[J].Ultrasonics,2000(1/8):503-507. |
| [11] | Mallat S.G.;Zhifeng Zhang .Matching pursuits with time-frequency dictionaries[J].IEEE Transactions on Signal Processing: A publication of the IEEE Signal Processing Society,1993(12):3397-3415. |
| [12] | MALLAT S G.A Wavelet Tour of Signal Processing[M].北京:机械工业出版社,2003 |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%