• John, Nigel St
• Wang, Chun
• Blacklock, Matthew
• Varley, Russell

Abstract

<p>Damping and stiffness are two key structural properties that tend to be mutually exclusive; stiff materials have low damping, whereas highly damped materials lack rigidity. The present work aims to investigate the effectiveness of cork material in improving the product of the stiffness and damping ratio of composite materials for structural applications. In this study, cork is incorporated into a carbon-epoxy composite using two methods: as a single constrained layer and micron-scale particulate inclusions. Damping performance is evaluated in terms of loss modulus which is the product of stiffness and loss factor, Eη. The loss modulus captures the reduction in stiffness, due to the introduction of a lossy material to improve the damping properties. Damping performance is found to increase with the introduction of cork material either as a constrained layer and particulates in the matrix at the first four natural frequencies. This presents the opportunity, particularly with the highly customizable particulate hybrid composite, for tailored structural materials with superior damping performance without degrading stiffness.</p>

Topics

• impedance spectroscopy
• polymer
• Carbon
• inclusion
• composite