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Title: The Influence of Inspection Angle, Wave Type and Beam Shape on Signal-to-Noise Ratios in Ultrasonic Pitch-Catch Inspections

Abstract

Grain noise, which arises from the scattering of sound waves by microstructure, can limit the detection of small internal defects in metal components. Signal-to-noise (S/N) ratios for ultrasonic pitch/catch inspections are primarily determined by three factors: the scattering ability of the defect; the inherent noisiness of the microstructure (per unit volume); and finite-beam effects. An approximate single-scattering model has been formulated which contains terms representing each of these factors. In this paper the model is applied to a representative pitch/catch inspection problem, namely, the detection of a circular crack in a nickel cylinder. The object is to estimate S/N ratios for various choices of the inspection angle and sonic wave types, and to demonstrate how S/N is determined by the interplay of the defect, microstructure, and finite-beam factors. We also explore how S/N is influenced by the sizes, shapes, and orientations of the transmitter and receiver sound beams.

Authors:
; ;  [1]
  1. Center for Nondestructive Evaluation, Iowa State University, Ames, IA 50011 (United States)
Publication Date:
OSTI Identifier:
21054975
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718022; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRACKS; DATA PROCESSING; DEFECTS; DETECTION; MICROSTRUCTURE; NICKEL; NICKEL ALLOYS; NOISE; ORIENTATION; PITCHES; SCATTERING; SIGNAL-TO-NOISE RATIO; SOUND WAVES; ULTRASONIC TESTING

Citation Formats

Margetan, F. J., Li Anxiang, and Thompson, R. B.. The Influence of Inspection Angle, Wave Type and Beam Shape on Signal-to-Noise Ratios in Ultrasonic Pitch-Catch Inspections. United States: N. p., 2007. Web. doi:10.1063/1.2718022.
Margetan, F. J., Li Anxiang, & Thompson, R. B.. The Influence of Inspection Angle, Wave Type and Beam Shape on Signal-to-Noise Ratios in Ultrasonic Pitch-Catch Inspections. United States. doi:10.1063/1.2718022.
Margetan, F. J., Li Anxiang, and Thompson, R. B.. Wed . "The Influence of Inspection Angle, Wave Type and Beam Shape on Signal-to-Noise Ratios in Ultrasonic Pitch-Catch Inspections". United States. doi:10.1063/1.2718022.
@article{osti_21054975,
title = {The Influence of Inspection Angle, Wave Type and Beam Shape on Signal-to-Noise Ratios in Ultrasonic Pitch-Catch Inspections},
author = {Margetan, F. J. and Li Anxiang and Thompson, R. B.},
abstractNote = {Grain noise, which arises from the scattering of sound waves by microstructure, can limit the detection of small internal defects in metal components. Signal-to-noise (S/N) ratios for ultrasonic pitch/catch inspections are primarily determined by three factors: the scattering ability of the defect; the inherent noisiness of the microstructure (per unit volume); and finite-beam effects. An approximate single-scattering model has been formulated which contains terms representing each of these factors. In this paper the model is applied to a representative pitch/catch inspection problem, namely, the detection of a circular crack in a nickel cylinder. The object is to estimate S/N ratios for various choices of the inspection angle and sonic wave types, and to demonstrate how S/N is determined by the interplay of the defect, microstructure, and finite-beam factors. We also explore how S/N is influenced by the sizes, shapes, and orientations of the transmitter and receiver sound beams.},
doi = {10.1063/1.2718022},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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