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Scanning laser techniques for characterisation of different surface breaking defect geometries

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Hernandez-Valle, Francisco, Edwards, R. S. (Rachel S.), Clough, A. R., Rosli, M. H. and Dutton, B. (Ben) (2012) Scanning laser techniques for characterisation of different surface breaking defect geometries. In: 18th World Conference on Non-Destructive Testing, Durban, South Africa, 16th-20th April 2012. Published in: Proceedings : 18th World Conference on Non-Destructive Testing

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Official URL: http://www.ndt.net/article/wcndt2012/general.htm

Abstract

Measurements using a laser scanning system consisting of a pulsed Nd:YAG laser to generate surface ultrasonic
waves and an interferometer to detect the surface displacement, are presented for different samples and defect geometries. We show, ﬁrstly, details of the interaction of Rayleigh waves in thick samples with machined slots inclined at an angle to the surface normal, or with simple branched geometries, scanning the generation source over the defect (SLLS) or scanning the detection point over the defect (SLD). Secondly, we discuss effects of Lamb waves interacting with V-shaped defects in thin samples. The results from these measurements have shown that the signal enhancement found in the near-ﬁeld in both cases can be used to position the defect and gain an idea of its geometry, and have shown this to be a suitable ﬁngerprint of the presence of the defect.

Item Type:

Conference Item (Paper)

Subjects:

Q Science > QC Physics

Divisions:

Faculty of Science > Physics

Library of Congress Subject Headings (LCSH):

Ultrasonic waves, Nondestructive testing, Surfaces (Technology) -- Defects, Ultrasonic testing

Journal or Publication Title:

Proceedings : 18th World Conference on Non-Destructive Testing

Publisher:

South African Institute for Non-Destructive Testing (SAINT)

Official Date:

April 2012

Dates:

Date	Event
April 2012	Published

Status:

Not Peer Reviewed

Publication Status:

Published

Funder:

European Research Council (ERC)

Grant number:

202735 (ERC)

Conference Paper Type:

Paper

Title of Event:

18th World Conference on Non-Destructive Testing

Type of Event:

Conference

Location of Event:

Durban, South Africa

Date(s) of Event:

16th-20th April 2012

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