Application of the Eddy Current method and bragg grating optical sensors for the non destructive testing of bonded composite repairs

dc.contributor.author	Τσαμασφύρος, Γιώργος	el
dc.contributor.author	Κανδεράκης, Γιώργος	el
dc.contributor.author	Ντρίβας, Νικόλαος	el
dc.contributor.author	Πρασσιανάκης, Ιωάννης	el
dc.date.accessioned	2015-04-24T09:23:17Z
dc.date.available	2015-04-24T09:23:17Z
dc.date.issued	2015-04-24
dc.identifier.uri	http://hdl.handle.net/11400/8837
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://www.ndt.net/article/ENDTdays2007/nde_for_safety/appendix.pdf	en
dc.subject	Nondestructive testing
dc.subject	Eddy-current
dc.subject	Μη καταστροφικοί έλεγχοι
dc.subject	Δινορρεύματα
dc.title	Application of the Eddy Current method and bragg grating optical sensors for the non destructive testing of bonded composite repairs	en
heal.type	conferenceItem
heal.classification	Science
heal.classification	Physics
heal.classification	Επιστήμες
heal.classification	Φυσική
heal.classificationURI	http://skos.um.es/unescothes/C03532
heal.classificationURI	http://skos.um.es/unescothes/C02994
heal.classificationURI	N/A-Επιστήμες
heal.classificationURI	N/A-Φυσική
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh85092221
heal.language	en
heal.access	free
heal.recordProvider	Τ.Ε.Ι Αθήνας. Σχολή Τεχνολογικών Εφαρμογών. Τμήμα Φυσικής - Χημείας (πρώην).	el
heal.publicationDate	2007
heal.bibliographicCitation	Tsamasphyros, G., Kanderakis, G., Drivas, N. and Prassianakis, I. (November 2007). Application of the Eddy Current method and bragg grating optical sensors for the non destructive testing of bonded composite repairs. In the 37th International CNDT Annual Conference. Prague, 7th-9th November 2006. Available from: http://www.ndt.net/article/ENDTdays2007/nde_for_safety/appendix.pdf	en
heal.abstract	The increasing demand for life extension of both military and civil aircrafts led to significant advances in repair technology of cracked metallic structures. Consequently, bonded composite repairs of metallic structures became a rapidly growing technology in the field of aerospace. Given the specific characteristics of a bonded composite repair and the differences in the materials used in each case (metal, composite & adhesive), the applicability of a number of Non Destructive Testing methods to trace crack propagation under a composite patch repair of a cracked metallic structure is examined, following mechanical testing in fatigue. In this paper, the main NDT methods examined include the eddy current method applied over a bonded composite repair (i.e. without removing the repair) as well as Bragg grating optical sensors embedded into composite patches. The capability and the reliability of the eddy-current method to detect cracks under a composite obstacle of significant thickness were checked for several patch thickness. The eddy-current method was found to be fully capable of tracing the crack propagation under the composite patch, requiring only proper calibration of the generator. Small differences in the crack lengths between the patched and the unpatched side of the specimen which were examined were explained by their nonsymmetric configuration, which induced different stress intensity factors at the patched and the unpatched sides, as finite element analysis has clearly shown. On the other hand, Bragg grating sensors were proven capable of tracing crack propagation with high accuracy, through interpretation of the differences caused in the strain field over the crack, after comparison with finite element analysis results.	en
heal.fullTextAvailability	false
heal.conferenceName	International CNDT Annual Conference	en
heal.conferenceItemType	full paper