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Title: Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT

Abstract

Accurate measurement of strip thickness is a very high priority for the aluminium rolled product industry. This paper presents the findings of trials to measure the thickness of aluminium strip using a send-receive, radially polarised Electromagnetic Acoustic Transducer (EMAT). A broadband EMAT system, developed at Warwick University, UK with a centre frequency of approximately 5 MHz and frequency content up to 12 MHz was used. The resultant ultrasonic waveforms have been processed using Fourier analysis. Static measurements of aluminium alloy samples in the thickness range between 0.28 mm to 2.8 mm have been measured using this non-contact approach at stand-offs of up to 2 mm. Measurements across the aluminium strip width to evaluate its profile for quality control was also carried out successfully. Some of the experiments and results obtained are described in detail.

Authors:
;  [1]
  1. Novelis Inc., Novelis Global Technology Centre, Kingston, Ontario, K7L 5L9 (Canada)
Publication Date:
OSTI Identifier:
20798244
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 820; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Brunswick, ME (United States), 31 Jul - 5 Aug 2005; Other Information: DOI: 10.1063/1.2184735; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; ALUMINIUM ALLOYS; FOURIER ANALYSIS; MHZ RANGE 01-100; QUALITY CONTROL; TRANSDUCERS; WAVE FORMS

Citation Formats

Hobbis, A., and Aruleswaran, A.. Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT. United States: N. p., 2006. Web. doi:10.1063/1.2184735.
Hobbis, A., & Aruleswaran, A.. Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT. United States. doi:10.1063/1.2184735.
Hobbis, A., and Aruleswaran, A.. Mon . "Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT". United States. doi:10.1063/1.2184735.
@article{osti_20798244,
title = {Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT},
author = {Hobbis, A. and Aruleswaran, A.},
abstractNote = {Accurate measurement of strip thickness is a very high priority for the aluminium rolled product industry. This paper presents the findings of trials to measure the thickness of aluminium strip using a send-receive, radially polarised Electromagnetic Acoustic Transducer (EMAT). A broadband EMAT system, developed at Warwick University, UK with a centre frequency of approximately 5 MHz and frequency content up to 12 MHz was used. The resultant ultrasonic waveforms have been processed using Fourier analysis. Static measurements of aluminium alloy samples in the thickness range between 0.28 mm to 2.8 mm have been measured using this non-contact approach at stand-offs of up to 2 mm. Measurements across the aluminium strip width to evaluate its profile for quality control was also carried out successfully. Some of the experiments and results obtained are described in detail.},
doi = {10.1063/1.2184735},
journal = {AIP Conference Proceedings},
number = 1,
volume = 820,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2006},
month = {Mon Mar 06 00:00:00 EST 2006}
}
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