Optimization of the piezoelectric response of 0-3 composites: a modelling approach.
Résumé
Finite element modeling is used in this study to optimize the electromechanical behavior of 0-3 composites according to the material properties of their constituents. Our modeling approach considers an 'extended' 2D representative volume element (RVE) with randomly dispersed piezoelectric particles. A variable distribution of their polarization axes is also implemented because a full periodic arrangement of fillers and a unique poling orientation are unrealistic in practice. Comparisons with a simpler RVE and with an analytical model based on the Mori-Tanaka approach are performed as a function of the particle concentration for the elastic, dielectric and piezoelectric homogenized properties. An optimization of the piezoelectric response of 0-3 composites according to material considerations is then computed, allowing it to be shown that the piezoelectric strain coefficient is not the only relevant parameter and that lead-free piezoelectric fillers such as LiNbO3 and ZnO are competitive alternatives. Finally, the piezoelectric responses of 0-3 composites with different filler arrangements are quantitatively compared to 1-3 composites and to the corresponding bulk material.