Vibration characteristics of skew sandwich plates with functionally graded metal foam core

Current study deals with the free vibration analysis of skew sandwich plates. The sandwich plate is composed of three layers where the core layer is made from a metal foam while the faces are made from pure metal. Different types of functionally graded patterns are assumed for the distribution of pores in the core. The governing equations of the plate are obtained by means of the first order shear deformation theory. An oblique coordinate system is also defined and the basic governing equations are transformed from the orthogonal system to the oblique one. With the general idea of Ritz method where the shape functions are constructed by means of the Chebyshev polynomials, the matrix representation of the governing equations is established and an eigenvalue problem is extracted. Results of this study are given to discuss the effects of patterns and size of pores, boundary conditions, skew angle, host to face thickness ratio and aspect ratio of the plate. It is shown that all of these parameters are important on natural frequencies of the plate.