Performance of volume average scale linking in a strongly-coupled two-scale finite element methodology for polycrystalline solids

Strongly-coupled multi-scale simulations of polycrystalline solids, in which information between scales is transferred on-the-fly as needed, have gained attention as the scientific computing environment improves. Such simulations are performed combining the benefits from different scales to understand and predict the behavior of polycrystalline solids. In this research, two issues in averaging the crystal scale behavior used for the continuum scale calculation are investigated. First, the volume average polycrystal stress is compared with the surface average polycrystal stress at a material point in the continuum scale. Second, the accuracy of using the volume average polycrystal stiffness as a material stiffness in the continuum scale is investigated. The comparisons are carried out for simulation results from coupon-like specimens of two-phase polycrystalline materials under uniaxial tension. Results show that the approximate volume average stiffness and stress at the crystal scale provides adequate accuracy.