Vibration damping properties of steel/rubber/composite hybrid structures

By using hybrid structures, attractive and advantageous combinations of material properties can be achieved. In addition to the combination of good mechanical properties and low weight, also dynamical properties can be enhanced by suitable materials selection. However, the hybrid structure properties depend on the properties of the constituent materials as well as on the interfacial properties. In the present study, the damping properties of laminated structures consisting of steel, rubber or epoxy adhesive and glass fibre reinforced epoxy composite were studied. Damping properties of the structures were investigated through the loss factors. The loss factors of the hybrid structures and the constituent materials were determined by frequency and time domain test methods. By using the loss factor results of the constituent materials, the loss factor of the hybrid structures were estimated by the rule of mixtures and the results were compared with the experimental results. It was observed, that the use of weight fractions instead of volume fractions in the rule of mixtures provides a good average estimation of the damping behaviour of the hybrid structure and the results of rule of mixtures method can be used as rough estimates during the design phase of hybrids of this kind.