Calculation of Dispersion Curves in the Composite Graphite-Epoxy Plate by a Hybrid Analytic Method

In recent years, graphite-epoxy materials have been widely used in the space industry due to their ability to satisfy design demands (minimum weight and high structural rigidity). However, radiation resulting from the space environment can create imperfections in these structures. The ultrasonic non-destructive testing by guided wave presents an alternative for the detection of these defects. The knowledge of the dispersion curves is an essential step in order to know the adequate frequencies susceptible to propagate in our material for a successful control. In this manuscript, we present a hybrid analytical method to plot the dispersion curves of a graphite-epoxy composite material. The advantage of this method over the classical analytical methods has been studied. The accuracy of the obtained results is controlled using the DISPERSE software. Next, the profiles of the displacements and stresses normalized by the acoustic power flow of the fundamental modes are plotted at a given frequency. A discussion of the vibratory states of the plate is established.