Elastic constants of polycrystals with generally anisotropic crystals

A homogenization model is developed that describes the effective elastic constants ofpolycrystallinematerials with constituent crystallites of generalanisotropy (triclinic symmetry). The model is solved through an iterative technique where successive iterations improve the estimates of the polycrystal's elastic constants. Convergence of the solution provides the self-consistent elastic constants, which are the polycrystal's elastic constants resulting from continuity between local and far-fieldstress and strains. Iterative solutions prior to convergence are the bounds on the elastic constants including the Voigt-Reuss and Hashin-Shtrikman bounds. The second part of the article establishes a formal link between the present model andsingle-crystal elasticanisotropy. Ananalysis from a dataset containing 2176 inorganic crystallinecompounds, spanning all crystallographic symmetries, is provided. The role of elasticanisotropy and related properties such as crystallinestructure and elastic stability are discussed as it relates to the model.

Source: Journal of Applied Physics - October 26, 2016 Category: Physics Authors: Christopher M. Kube and Maarten de Jong Source Type: research