A microstructure-based approach to modeling electrostriction that accounts for variability in spatial locations of domains

摘要: Abstract The discovery of polyvinylidene fluoride (PVDF) based family relaxor ferroelectric (RFE) polymers has attracted attention due to their high electrostrictive strain and relatively low hysteresis loss. These RFE exhibit complex microstructures containing both crystalline domains amorphous domains; the interactions drive behavior these EAPs, while dictate mechanical materials. Furthermore, are spatially orientationally distributed across medium, further complicating morphology polymers. Although a number studies have focused on experimental computational investigation interaction among different phases this RFE, electrostriction models that represent variabilities in microstructure biphasic lacking. proposed model aims link semicrystalline observed electromechanical coupling. An energy density function is constructed for representative volume element (RVE) EAP, including term each phase, amorphous. Coulomb between pair dipoles. responses predicted by modified hyperelastic stress–stretch eight-chain model. total free then analyzed under constitutive laws an isothermal deformation determine stresses generated RVE. versus electric field, i.e. electrostriction, relationship calculated from self-equilibrium condition Cauchy stress. material taken into account applying dipolar network model, which dipole represents domain surrounded medium. RVE experiences with neighboring crystallites, drives material. Two basic cases explored study effects spatial variation locations relative other. higher fidelity descriptions location introduced through addition probability (PDF) dipoles around central dipole. Comparing results literature allows best-fit determination parameters describing PDF, e.g. aspects microstructure, itself. results, agree well data, imply ability infer key information about fitting distribution single adjustable parameter. unique its amenable direct measurement spectroscopic scattering techniques. Consequently, linked physical characteristics quantifiable, such as magnitudes moments parameters.The may also be used elucidate using best fit physically meaningful possibly providing processing-structure-property relationships future researchers.