Approach to optimize poling conditions of metal matrix piezoelectric composite

An approach for optimizing the poling conditions of metal matrix piezoelectric composite (MMPC) using a series capacitor model is proposed and its verification is performed. The oxide film formed around the electrodes in MMPC is necessary for insulation between the electrodes and the metal matrix, however, during the poling process, the oxide film deprives the polarizing electric field and prevents polarization of piezoelectric ceramics. Therefore, a method to optimize the polarizing voltage using the thickness and dielectric constant of the oxide film in a series capacitor model with a simplified structure of the MMPC is required. In addition, the validity of the proposed method is investigated by output voltage obtained from fabricated composites that performed the poling process. The results of the optimization show that optimal polarization is not possible with the Ni and Ti oxide films used in this study. However, the results of the polarization treatment of the actual composite material confirmed the validity of the proposed method, as the output voltage improvement is in line with the proposed method.