Voltage-induced deformation in dielectric

When subjected to a high electric field, dielectrics deform. For a hard dielectric, voltage-induced deformation is usually small, and the potential for deformation is determined by its breakdown voltage. If a dielectric is soft, the voltage-induced deformation is significantly large. The potential for deformation is determined by the breakdown voltage together with electromechanical instability and snap-through instability. Based on the theoretical researches conducted by Zhao and Suo [Phys. Rev. Lett. 104, 178302 (2010)] and Li [Int. J. Smart Nano Mater. 2(2), 59-67 (2011)], taking the dielectric elastomer soft material as research object, we introduce three kinds of material limits: strain-stiffening, polarization saturation, and breakdown voltage. The effect of material limits on voltage-induced deformation is analyzed. Also investigated is the influence of pre-stretch and material parameters on the deformation. For a specific soft dielectric material under certain pre-stretch, the theoretical maximum electrical actuation deformation can be determined.