Prediction of reflection amplitudes for ultrasonic inspection of rough planar defects
File(s)
Accepted version
Author(s)
Haslinger, SG
Lowe, MJS
Craster, R
Huthwaite, P
Shi, F
Type
Journal Article
Abstract
The characteristics of planar defects (no loss of material volume) that arise during industrial plant operation are difficult to predict in detail, yet these can affect the performance of non-destructive testing (NDT) used to manage plant structural integrity. Inspection modelling is increasingly used to design and assess ultrasonic inspections of such plant items. While modelling of smooth planar defects is relatively mature and validated, issues have remained in the treatment of rough planar defect species. The qualification of ultrasonic inspections for such defects is presently very conservative, owing to the uncertainty of the amplitudes of rough surface reflections. Pragmatic solutions include the addition of large sensitivity thresholds and more frequent inspection intervals, which require more plant downtime. In this article, an alternative approach has been developed by the authors to predict the expected surface reflection from a rough defect using a theoretical statistical model. Given only the frequency, angle of incidence and two statistical parameter values used to characterise the defects, the expected reflection amplitude is obtained rapidly for any scattering angle and size of defect, for both compression and shear waves. The method is applicable for inspections of isotropic media that feature surface reflections such as pulse-echo or pitch-catch, rather than for tip signal-dependent techniques such as time-of-flight diffraction. The potential impact for inspection qualification is significant, with the new model predicting increases of up to 20 dB in signal amplitude in comparison with models presently used in industry. All mode conversions are included and rigorous validations using numerical and experimental methods have been performed. The model has been instrumental in obtaining new statistically significant results related to the effect of tilt; the expected pulse-echo backscattered amplitude for very rough planar defects is independent of tilt angle, with convergence obtained for a range of frequencies.
Date Issued
2021-01-01
Date Acceptance
2021-01-01
Citation
Insight, 2021, 63 (1), pp.28-36
ISSN
2156-485X
Publisher
Wiley-Blackwell
Start Page
28
End Page
36
Journal / Book Title
Insight
Volume
63
Issue
1
Copyright Statement
© 2021 Ingenta. Article copyright remains with the publisher, society or author(s) as specified within the article.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Imperial College Trust
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000611155100006&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
EP/M020207/1
PC2508ICT
EP/L022125/1
EP/P01951X/1
Subjects
Science & Technology
Technology
Instruments & Instrumentation
Materials Science, Characterization & Testing
Materials Science
SURFACES
SIMULATIONS
SCATTERING
SMOOTH
MODEL
Publication Status
Published
Date Publish Online
2021-01-01