Acoustical Guided Waves in Inhomogeneous Cylindrical Materials

Study of guided waves in inhomogeneous elastic bodies has been an important area of solid mechanics for well over a century. Initial studies in the plates were applied to analyze surface acoustic waves in semi-infinite substrates and multilayered structures. Recently, several investigations have been reported on the axial propagation of guided waves in Functionally Graded Materials (FGMs). An FGM is essentially an inhomogeneous material composite, made up of two or more materials chosen to obtain desirable properties for specific applications. In this study, properties of the material such as Young's modulus, Poisson's ratio and mass density, are assumed to vary in the direction of the thickness according to a known radial variation law. Normalized frequencies of the guided acoustic modes are calculated as a function of normalized thickness. Dispersion curves and field profiles are presented for certain specific modes. The developed software is capable of dealing efficiently and accurately with a variety ...