Propagation of laser-generated visco-elastic Rayleigh-like waves in coatings

This paper reports on a study of the propagation characteristics of visco-elastic, Rayleigh-like waves in coatings. Beginning with the Kelvin model, the characterization equation and the normal displacement of visco-elastic Rayleigh waves in stratified half-space structures are derived and the influence of the visco-elastic modulus on dispersion and attenuation are discussed. The transient response of a visco-elastic Rayleigh wave is also simulated by means of Laplace and Hankel inversion transforms. The results are in good agreement with the theoretic predictions. It is believed the paper´s results and conclusions will provide insights and guidance for estimating visco-elastic parameters.