Nondestructive Evaluation of Temporarily Repaired CFRP Laminates Subjected to Delaminations due to Localized Heating and Cyclic Loading Combined

  • Han, Tae-Young (Graduate School, Department of Mechanical Engineering, Inha University) ;
  • Kwon, Oh-Yang (Department of Mechanical Engineering, Inha University)
  • Published : 2007.06.30

Abstract

The reliability of cold-bonding repair technique of carbon-fiber reinforced plastics (CFRP) laminates, often used as a temporary repair for the airplane maintenance, has been evaluated during cyclic loading and localized heating by nondestructive methods. Major concern was given to the evolution of damage after repair in the form of delaminations due to localized heating and cyclic loading combined. An area of interest both on the specimen repaired by cold-bonding and the specimen without repair where delaminations were induced by localized heating and cyclic loading was monitored by acoustic emission (AE) testing and further examined by pitch-catch low-frequency bond testing, and pulse-echo high-frequency ultrasonic testing. The results showed that the reliability of cold-bonding repair would be significantly reduced by the localized heating and cyclic loading combined rather than by the cyclic loading only. AE monitoring appeared to be an effective and reliable tool to monitor the integrity of temporarily repaired CFRP laminates in terms of the structural health monitoring (SHM) philosophy.

Keywords

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