Analysis of laser-generated viscoelastic Rayleigh wave on viscoelastic materials

The propagation characteristics of viscoelastic Rayleigh wave are studied theoretically. Based on general viscoelastic theory, the frequency equation and the normal displacement of viscoelastic Rayleigh wave are derived, the influence of the viscoelastic modulus on dispersion and attenuation is discussed. We found the effect of viscosity on dispersion curves is small relatively, but its effect on attenuation is directly proportional to viscosity modulus in the case of little viscosity, the effect of shear viscosity on attenuation curves is much more than that of bulk viscosity. The transient waveforms of viscoelastic Rayleigh wave are also simulated, which are showed in good agreement with the theoretic predictions.