Determination method of constitutive model parameters of dielectric elastomer material

The energy conversion process of dielectric elastomers is an electromechanical coupling behavior, and the constitutive model of the material is the basis for studying electromechanical coupling characteristics. In order to explore the constitutive model of dielectric elastomers, based on the theory of continuum mechanics, combined with the superelastic constitutive model, a mechanical constitutive model was described, and the basic equations of the constitutive model were obtained. At the same time, combined with uniaxial, biaxial, and pure shear stretching, the three tensile methods, the relationship between the tensile rate and the force of the dielectric elastomer under three kinds of stretching modes was obtained. The experimental data were fitted by the COMSOL software, and the fitting curves of the relationship between stress and elongation of four superelastic models were obtained. Comparative analysis of the experimental data and fitted curve showed that the Neo-Hookean model had the worst fitting effect. The Yeoh model and the Ogden model had better shear fitting. The Mooney-Rivlin model fitted well in the three stretching modes. The conclusions of this study provided the basis for the study of the electromechanical coupling characteristics of dielectric elastomers.