Title
Defect Detection In Aerospace Sandwich Composite Panels Using Conductive Thermography And Contact Sensors
Abstract
Sandwich panels consisting of two Carbon Fibre Reinforced Polymer (CFRP) outer skins and an aluminium honeycomb core are a common structure of surfaces on commercial aircraft due to the beneficial strength-weight ratio. Mechanical defects such as a crushed honeycomb core, dis-bonds and delaminations in the outer skins and in the core occur routinely under normal use and are repaired during aerospace Maintenance, Repair and Overhaul (MRO) processes. Current practices rely heavily on manual inspection where it is possible minor defects are not identified prior to primary repair and are only addressed after initial repairs intensify the defects due to thermal expansion during high temperature curing. This paper reports on the development and characterisation of a technique based on conductive thermography implemented using an array of single point temperature sensors mounted on one surface of the panel and the concomitant induced thermal profile generated by a thermal stimulus on the opposing surface to identify such defects. Defects are classified by analysing the differential conduction of thermal energy profiles across the surface of the panel. Results indicate that crushed core and impact damage are detectable using a stepped temperature profile of 80 degrees C The method is amenable to integration within the existing drying cycle stage and reduces the costs of executing the overall process in terms of time-to-repair and manual effort.
Year
DOI
Venue
2020
10.3390/s20226689
SENSORS
Keywords
DocType
Volume
aerospace composite, dis-bond, honeycomb, impact damage, maintenance repair overhaul, non destructive inspection, quality assurance, re-manufacture, sandwich structure, thermography
Journal
20
Issue
ISSN
Citations 
22
1424-8220
0
PageRank 
References 
Authors
0.34
0
7
Name
Order
Citations
PageRank
David I. Gillespie100.68
Andrew Hamilton2414.09
R. C. Atkinson312918.38
Xavier J. A. Bellekens45811.68
Craig Michie5155.78
Ivan Andonovic66016.05
christos tachtatzis79114.27