Micro-electromechanics models for piezoelectric-fiber-reinforced composite materials

In this paper, two micro-electromechanics models, i.e. a rectangle model and a rectangle-cylinder model, are proposed for predicting the elastic, piezoelectric and dielectric constants for piezoelectric-fiber-reinforced composite (PFRC) materials under both single load and multiple load conditions. The closed-form formulae for these two models are derived by using a linear piezoelectric theory and iso-field assumptions. A comparison is carried out for the electroelastic constants predicted by the rectangle model under single load and multiple load conditions. A numerical study is also conducted to investigate the effects of geometrical parameters on the effective electroelastic constants, and to discuss the convergence of the rectangle-cylinder model. The results predicted using the present rectangle and rectangle-cylinder models correlate favorably with the finite-element analysis (FEA) results for the elastic constants, and with the existing experimental results for d33 and ε33T/εo.