A higher-grade theory of non-ferromagnetic thermo-elastic dielectrics which incorporates the local mass displacement, the heat flux gradient, polarization inertia, and flexodynamic effects is developed. The process of local mass displacement is associated with changes in material microstructure. Using the fundamental principles of continuum mechanics, electrodynamics, and non-equilibrium thermodynamics, the gradient-type constitutive equations are derived. Due to accounting for the polarization inertia, the rheological constitutive equation for the polarization vector is obtained. In the balance equation of linear momentum, an additional term with the second time derivative of the polarization vector appears in comparison with the classical theory. This term controls the influence of the dynamic flexoelectric effect on the mechanical motion of dielectric solids. The propagation of a plane harmonic wave is analyzed within the context of the developed theory. It is shown that the theory allows for capturing the experimentally observed phenomenon of high-frequency dispersion of a longitudinal elastic wave. The theory may be useful for modeling coupled processes in nanodielectrics and heterogeneous polarized systems.

开发了一种更高级的非铁磁热弹性电介质理论，该理论结合了局部质量位移、热通量梯度、极化惯量和挠曲动力学效应。局部质量位移的过程与材料微观结构的变化有关。利用连续介质力学、电动力学和非平衡热力学的基本原理，推导了梯度型本构方程。由于考虑了极化惯量，得到了极化矢量的流变本构方程。在线性动量平衡方程中，与经典理论相比，增加了偏振矢量二阶时间导数项。该项控制动态挠曲电效应对介电固体机械运动的影响。在所发展的理论的背景下分析了平面谐波的传播。结果表明，该理论可以捕获实验观察到的纵向弹性波高频色散现象。该理论可用于模拟纳米电介质和异质极化系统中的耦合过程。