Dynamic stability of piezoelectric braided composite plates

Three-dimensional braided composites are a class of textile composite materials with a fully integrated, continuous spatial fiber network that eliminates the interface problem by the inter-lacing of the tows in the thickness direction. These braided composites have attracted considerable attention in recent years due to their unique advantages such as low fabrication cost, improved flexure strength, and higher impact resistance. This paper presents a dynamic stability analysis of a simply supported 3D braided composite laminated plate with surface-bonded piezoelectric layers and subjected to electrical and periodic in-plane mechanical loads. A fiber inclination model is used to predict the effective stiffness matrices of the braided composite laminates. Theoretical formulations are based on higher-order shear deformation plate theory and include piezoelectric effects. Double Fourier series is employed to convert the dynamic governing equations into a linear system of Mathieu-Hill equations from which the boundary points on the unstable regions are determined by Bolotin's method. Numerical illustrations are given in both tabular and graphical forms, showing the influence of fiber volume fraction, braiding angle, inclination angle, static load level, applied voltage, and aspect ratio on the dynamic stability of the braided composite plate.