Effect of roughness on the elastic surface wave propagation

Abstract

We have supposed a new approach for the investigations of the effect of roughness on the propagation of the elastic surface waves. The presence of the rough layer is accounted by the modification of the boundary conditions. In the framework of this approach we have investigated the propagation of Rayleigh waves on an isotropic substrate having rough surface. It is shown that the roughness leads to the linear dispersion of the phase velocity of the surface waves, which are non dispersive on the ideal surfaces. Also we have investigated the influence of a rough surface of films, deposited on the substrate. The roughness of the film surface produces contributions to the phase velocities of Love and Rayleigh modes. In all cases the contributions are proportional to the effective thickness of the rough layer. It is shown that the effect of the rough layer is equivalent to the effect of a thin film, having loading characteristic. The approach can be used for investigations of the effect of roughness on the propagation of surface waves on the rough surface of the anisotropic crystals.