Evaluation of Tensile Strength on Repaired Composite Adhesive Bonded Joint

The present work is to study the tensile strength behavior of the repaired material on low velocity impact damaged GFRP laminate using various repair techniques and prediction of their strength through the experimental investigation. While the servicing life of aircraft structures were damaged by the impact damages such as foreign objects collision, mishandlings of tools etc. During the Impact event the laminate were going to cause deformations such as matrix cracking, fiber breaking, and delamination within the laminate. Practically, the damages in composites are unpredictable about their growth where it was using to predict through the ultrasonic A-scan technique. The test specimen made of bi-directional glass fiber and epoxy resin had an impact with a low velocity impact facility. The extent of damage is determined using ultrasonic scanning and the damaged layers were removed using grinding technique. The removed damaged region was repaired using single bonded lap and double bonded lap repair techniques were used to restore the structural integrity of the laminate. These repaired specimens were uniaxially loaded in INSTRON universal testing machine and the behaviors of adhesively bonded patches were studied using load versus displacement graph. From the observed experiments, the failure loads were compared with the strength of undamaged specimen. Using the obtained parameters the optimized repair technique was proposed. Ultimately this work can be used to improve the safety of composite structures while extending their period of service. 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Noorul Islam Centre for Higher Education