Propagation of Rayleigh Waves in Functionally graded Magneto-electro-elastic half-space

The propagation of Rayleigh-type waves is analytically and numerically investigated in this paper for a nonhomogeneous half-space with 6mm(hexagonal) symmetry. The piezoelectric, piezomagnetic, elastic parameters and density are all assumed to exponentially vary with depth. The dispersion relation for such waves has been obtained in a general form and solved numerically for a medium with a boundary free of mechanical stress. Rayleigh waves are seen to exist for certain electro-magnetic boundary conditions and these waves are dispersive, as opposed to non-dispersive waves in a homogeneous medium. In contrast with the case of non functionally-graded materials, non-homogeneity is seen to give rise to waves in several cases. The velocity and dispersion are also significantly affected by the non-homogeneity.