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Vol.11 No.4previousAA SP22 (AA165-166-167-168-169-170-171) NT96

Academic Articles
Regular Paper Vol. 11 No. 4 (2020) p.139 - p.146

Corrosion Induced Roughness Characterization by Ultrasonic Attenuation Measurement


Hiroyuki NAKAMOTO1,3,*, Philippe GUY2 and Toshiyuki TAKAGI3,4

1 Graduate School of System Informatics, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
2 Laboratoire Vibrations Acoustique, INSA-Lyon, 25 bis, av. J. Capelle F-69621 Villeurbanne Cedex, Lyon, France
Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
ELyTMaX UMI 3757, CNRS – Université de Lyon – Tohoku University, International Joint Unit, Université de Lyon, Lyon, France

Corrosion and erosion lead to partial wear inside pipes. This wear induces some roughness of the inner pipe wall and decreases its thickness. This could cause a fatal accident in nuclear and thermal power plants. In general, nondestructive inspection by ultrasonic devices measures only the thickness, not the roughness. When reflected on a rough surface ultrasonic waves scatter and attenuate. Then this study aims to estimate the surface roughness of the pipe wall from ultrasonic attenuation estimation, based on the analysis of the acquired waveforms on several specimens that have been machined in order to simulated a corroded rough surface. The experimental data exhibit a clear relationship between the roughness and the ultrasonic attenuation, in good agreement with theoretical models available in the literature, for both bulk longitudinal and shear waves.
Nondestructive testing, corrosion, surface roughness, wave attenuation, longitudinal and shear-horizontal wave
Full Paper: PDF
Article Information
Article history:
Received 28 November 2018
Accepted 03 February 2020