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The Role Of Grain Noise In Eddy Current Inspection Of Titanium Alloys

Published online by Cambridge University Press:  10 February 2011

M. P. Blodgett  and
P. B. Nagy
M. P. Blodgett
Affiliation:
Metals, Ceramics, and NDE Division, Air Force Research Laboratory, Ohio 45433
P. B. Nagy
Affiliation:
Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Ohio 45221
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Abstract

This paper discusses the role electrical anisotropy plays in the structural integrity assessment of polycrystalline titanium alloys from the standpoint of fatigue crack detection and the related issue of microstructural noise. In eddy current inspection of noncubic crystallographic classes of polycrystalline metals the electric anisotropy of individual grains produces an inherent microstructural variation or noise that is very similar to the well-known acoustic noise produced by the elastic anisotropy of both cubic and noncubic materials in ultrasonic characterization. The presented results demonstrate that although the electrical grain noise is detrimental in eddy current nondestructive testing for small flaws, it can be also exploited for characterization of the microstructure in noncubic polycrystalline materials such as titanium alloys in the same way acoustic grain noise is used for ultrasonic characterization of the microstructure in different materials.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 503: Symposium JJ – Nondestructive Characterization of Materials in Aging Systems , 1997 , 53
Copyright
Copyright © Materials Research Society 1998

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