In addition to the hexagonal crystals of class 6 mm, many piezoelectric materials (e.g., BaTiO3), piezomagnetic materials (e.g., CoFe2O4), and multiferroic com-posite materials (e.g., BaTiO3-CoFe2O4 composites) also exhibit symmetry of transverse isotropy after poling, with the isotropic plane perpendicular to the poling direction. In this paper, simple and elegant line-integral expressions are derived for extended displace-ments, extended stresses, self-energy, and interaction energy of arbitrarily shaped, three-dimensional (3D) dislocation loops with a constant extended Burgers vector in trans-versely isotropic magneto-electro-elastic (MEE) bimaterials (i.e., joined half-spaces). The derived solutions can also be simply reduced to those expressions for piezoelectric, piezo-magnetic, or purely elastic materials. Several numerical examples are given to show both the multi-field coupling effect and the interface/surface effect in transversely isotropic MEE materials.
This paper studies wave propagation in a soft electroactive cylinder with an under- lying finite deformation in the presence of an electric biasing field. Based on a recently proposed nonlinear framework for electroelastieity and the associated linear incremental theory, the basic equations governing the axisymmetric wave motion in the cylinder, which is subjected to homo- geneous pre-stretches and pre-existing axial electric displacement, are presented when the elec- troactive material is isotropic and incompressible. Exact wave solution is then derived in terms of (modified) Bessel functions. For a prototype model of nonlinear electroactive material, illus- trative numerical results are given. It is shown that the effect of pre-stretch and electric biasing field could be significant on the wave propagation characteristics.