Numerical characterization of quasi-longitudinal and quasi-shear waves in anisotropic polycrystalline microstructures with elongation and texture

Texture and grain elongation can occur in metallic microstructures due to various manufacturing processes, such as welding or rolling deformation. These microstructural characteristics generally lead to anisotropic macroscopic properties to which ultrasonic waves are particularly sensitive. It is therefore interesting to predict not only the speed but also the attenuation of these waves as a function of these microstructural properties. Finite Element Method has been applied to that aim in various works, mainly in the case of isotropic microstructures. Anisotropic microstructures raise specific challenges, including the random generation of samples, the handling of boundary effects, and the analysis of anisotropic modes. This communication details a method that addresses them. Results are presented for microstructures with elongation, texture, or both. Comparisons to analytical models are also provided.