Material failures in aircraft fuselage and mechanic tests of a repaired composite structure

In this thesis, material failures in aircraft fuselage and repair techniques arestudied. Following an introduction and literature review, failure controls and theirclassification in aircraft parts are investigated and general repair principals areexplained. Aircraft parts are checked periodically; failed parts are determined andclassified; and these parts are either repaired or replaced depending on type of thefailure. There are different methods of repair such as patch, reinforcement anddrilling for the repair of the failed part.The use of composite materials has been increased for decades, and failedcomposite parts have been repaired by bonding techniques. These parts arerepaired using different techniques such as metal-composite bonding, composite-composite bonding, co-curing bonding depending on their application. Repairwith bonding reduces number of parts and hence reduces the weight significantly.Furthermore it provides reduced repair time and repair ease.iiiMechanical performance of the bonded joints made from glass and carbon fibercomposites is investigated experimentally. Samples of single and double lap jointshave prepared, and were subject to tension and fatigue tests; the results of test arecompared. According to the results, although bonding provides high staticstrength, fatigue performance was low.2006, 132 pagesKey Words: Failure, repair, composite material, production techniques, fatiquetests, tension tests.iv