Experimental observations clearly show that the performance of dielectric elastomericbased
devices can be considerably improved using composite materials. A critical issue
in the development of composite dielectric materials toward applications is the
prediction of their failure mechanisms due to the applied electromechanical loads. In
this paper we investigate analytically the influence of electromechanical finite
deformations on the stability of multilayered soft dielectrics under plane-strain
conditions. Four different criteria are considered: (i) loss of positive definiteness of
the tangent electroelastic constitutive operator, (ii) existence of diffuse modes of
bifurcation (microscopic modes), (iii) loss of strong ellipticity of the homogenized
continuum (localized or macroscopic modes), and (iv) electric breakdown. While the
formulation is developed for generic isotropic hyperelastic dielectrics, results are
presented for the special class of ideal dielectrics incorporating a neo-Hookean elastic
response. The effect of material properties and loading conditions is investigated,
providing a detailed picture of the different possible failure modes.
