Damage tolerance in repaired composite laminates

Abstract

In order to alleviate the adverse impact of the air transport on the environment, the UE has shown great interest in increasing the efficiency and safety of aircrafts, which covers the complete life cycle of aircrafts (design, production, maintenance, repair and update).Composite structures show high susceptibility to low-velocity impacts in the perpendicual direction to the plane of the laminate. The complete replacement of damaged components is not always possible due to the high level of integration of the structures and the large size of the components in many sectors (i.e. aeronautics). In this regard, the repair and subsequent put into operation of structures made of composite materials must be a cost-effective and time-saving process.Adhesive repairs present advantages in relation to mechanical repairs. There is a lack of knowledge in their behaviour under impact loads; therefore, the main goal of this work is to analyse the damage tolerance of composite repaired structures. To this end, an experimental study has been carried out on intact and repaired laminate specimens that allows comparing the structural response of both configurations.This study involves the generation of damage through low-velocity impacts (using a drop-weight tower), and subsequent compression tests in order to determine their residual stenght.

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