Modeling of Hysteresis in Single-Crystalline Barium Titanate with Allowance for Domain Structure Evolution

The paper proposes a microstructural model of tetragonal single-crystalline barium titanate for analyzing how the state of its domain structure can influence the simulation accuracy of dielectric hysteresis curves with regard for domain interactions and for stress and electric field inhomogeneities in the single crystal. Hysteresis curves based on finite element homogenization are presented for all eight types of second-rank laminate domain patterns satisfying the compatibility conditions. It is shown that the properties of domain structures are substantially anisotropic under loading in different directions and that the dielectric hysteresis for different domain patterns differs greatly. The proposed model allows one to describe the effects of domain hardening and unloading nonlinearity. The results of calculations using the model agree well with experimental data at different cyclic load amplitudes.