Electromechanical Coupling Deformation And Energy Transition Behavior Of Dielectric Elastomer

With the further development of society and science, the troditional hardmaterials can no longer meet the needs of social production and daily life, while,at the same time, the intelligent soft material with large deformation shows itshuge advantages such as good biocompatibility, large deformation, high elasticenergy desity, quick response, light weight, cheap, easy for processing andmanufacturing et al, which leads the flexible devices made by soft materialspossessing huge application prospect in the fields of mechanics, medical treatment,military industry, aerospace and so on.As a kind of typical intelligent soft material, the electroactive polymerdielectric elastomer can produce large deformation and force under externalelectrical field, changing electrical energy into mechanical energy. Then, withoutthe electrical field, it can recover the original shape under elastic recovery effect,changing mechanical energy into electrical energy and storing. In this way, theinterconversion between mechanical force and electrical field is realized. Usingthis property we can design and manufacture actuators to realize electricalenergy-mechanical energy transition and we can also design and manufactureenergy harvestors, sensors to realize mechanical energy-electrical energy transition.The dielectric elastomer already becomes a kind of biomimetic material withinhuge application prospect and also a kind of revolutionary material being calledthe “artificial muscle”.In this paper, we investigate the electro-mechanical coupling deformation andenergy transition mechanism of dielectric elastomers, starting from the softmaterial mechanics, we explain the dielectric elastomer theory based on thethermodynamical framework and continuum mechanics model. Coupling withlarge deformation and electro-mechanical loads, we describe the nonliner behaviorof dielectric elastomer. The constitutive relation of dielectric elastomer is deducedand the failure modes of dielectric elastomer energy harvestor are discussed.Considering two kinds of material model respectively: the Mooney-Rivlin modeland the Gent model, combining with the strain hardening effect, polarizationsaturation effect, viscoelastic dissipation and electro-mechanical phase transition,we get the allowable area of dielectric elastomer energy harvestor and the maximalenergy that can be converted. These results have huge practical guide significancefor buliding more optimized energy harvesting cycling system and desigingdielectric elastomer energy harvestor for practical production.