Extending intergranular normal-stress distributions using symmetries of linear-elastic polycrystalline materials

Dr. Samir El Shawish from the Reactor Engineering Division at Jožef Stefan Institute published the research article “Extending intergranular normal-stress distributions using symmetries of linear-elastic polycrystalline materials” in Acta Mechanica, which is an international journal focused on theoretical and applied mechanics.

The paper presents a novel approach to model intergranular normal-stress distributions in linear-elastic polycrystalline materials when subjected to external forces. By leveraging symmetry-based arguments, this approach demonstrates that the stress distribution can be precisely reconstructed using only the first ten statistical moments. These moments are primarily influenced by three stress invariants and a few material invariants, reflecting the macroscopic polycrystalline isotropy and material linear behavior. This innovative technique facilitates the extension of known stress distributions under particular loading conditions to those under arbitrary conditions, and thus holds significant implications for probabilistic modeling of grain boundary damage in structural materials.

Figure: Intergranular normal-stress distributions (PDFs) for different loading conditions. A comparison is shown between PDFs obtained in simulations (black) and PDFs predicted by the new method (red) using N available distributions as input (bold black).