Theoretical and numerical simulation of bulk and surface ultrasonic waves scattering in microstructures with elongated grains

In the present work, the grain scattering induced attenuation coefficient is obtained for longitudinal bulk waves in untextured cubic polycrystalline materials with elongated grains using theoretical 2D and 3D proposed models. Also, a semi-analytical approach to estimate the attenuation of Rayleigh waves is used. Numerical simulations are done with a finite element code using a space-discontinuous Galerkin method and a Runge-Kutta time discretization scheme. The numerical and theoretical results are compared to study the influence of the grain shape/rotation on the attenuation coefficient.