Detection of Hidden Cracks on Aircraft LAP Joints with GMR Based Eddy Current Technology

Journal Article · Mon Mar 06 04:00:00 EST 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2184549· OSTI ID:20798254

Na, J K; Franklin, M A ^[1]; Linn, J R ^[2]

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1. Wyle Laboratories, Inc., 2700 Indian Ripple Road, Dayton, Ohio 45440 (United States)
2. Boeing Commercial Aviation Service, 2925 S 112th Street, Building 1114, Seattle, WA 98168 (United States)

Cracks occurring on commercial aircraft fuselage lap joints made of aluminum alloys often caused by scribe lines made during the removal of process of moisture sealing materials between two layers. These cracks on thinner bottom skin layers can be obscured by thicker top plates with paint. A portable GMR (Giant Magnetoresistive) sensor based eddy current system has been developed and tested on several simulated aircraft lap joints samples with EDM notches. Various thicknesses of layers are used to simulate the test as used on different combinations of lap joints. Length and depth of cracks are important factors for the safety of aircraft. Test results are used to come up with a portable nondestructive inspection system which is easy and fast with a high reliability of detecting cracks longer than a half inch in length and 0.010 inches in depth.

• OSTI ID: 20798254
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 820; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIRCRAFT
ALUMINIUM ALLOYS
CRACKS
EDDY CURRENT TESTING
JOINTS
LAYERS
MAGNETORESISTANCE
SEALING MATERIALS