Electro-mechanical bending analysis of ionic polymer metal nanocomposites (IPMNCs)

• A boundary value problem is discussed quantitatively using the nonlinear electro-elasticity.
• The equations are able to include softening of the material under applied voltages.
• The shift of the neutral axis is explained by a closed-form solution.
• The closed-form solution bridges between macroscopic and microscopic scales.
• The derived equations have no limitation for large deformations of thin and thick beams.

A nonlinear electro-elasticity formulation for a cantilever beam made of IPMNC is used to obtain constitutive equations. Using the measured experimental data, the constitutive parameters connecting the free energy to the beam characteristics are calibrated. The results show that the constitutive equations are able to include the softening behavior of the material under applied voltages as well as the shift of the bending neutral axis from the geometrical midline of the beam by a closed-form solution which bridges between macroscopic and microscopic scales. The equations consider large deformations of thin and thick beams.