Static and dynamic characterization of composition cork for sandwich beam cores

Abstract

Composition cork can be regarded as an interesting solution for light-damped sandwich panels. Despite the emergent interest on these materials for structural applications, there is a lack of information concerning its static and dynamic properties. This study presents a comparative study on a set of different experimental characterization methodologies applied on a selected agglomerated cork for vibration damping applications. The obtained results support the assumption of an air spring/viscous-based mechanism ruling the low-frequency behaviour of these materials. This assumed behaviour is a result from the observations of the cellular microstructure of natural and composition corks. Indicative values for the Young’s modulus, storage modulus and loss factor are provided as results from this study. In addition, a multilayer beam finite element, based on a mixed formulation, is proposed to be applied in an inverse characterization methodology and to be used also for the experimental validation tasks. The finite element proved to be efficient and accurate.