Piezoelectric and magnetic properties of PZT-(Ni0.284Zn0.549Cu0.183)Fe1.984O4 composites

The piezoelectric/piezomagnetic composite, PZT/Ni0.284Zn0.549Cu0.183Fe1.984O4, was fabricated by the mixed oxide method. The phase assemblage, piezoelectric strain constant and saturation magnetization were investigated. The results indicate that the PZT phase is compatible with Ni0.284Zn0.549Cu0.183Fe1.984O4 phase, and dense diphasic ceramic composites were obtained. It is found that piezoelectric strain constant decreases exponentially as the amount of doped piezomagnetic materials in the composite increases. Correspondingly, saturation magnetization of the composite also decreases with the increasing weight fraction of piezoelectric materials. Three reasons cause the results. First, the grain growth of piezomagnetic phase at the co-sintering temperature reduces grain size and continuity of the piezoelectric phase. Second, the pore size and porosity in composite increase dramatically with increasing amount of piezomagnetic phase. Third, the low resistivity of the composite prevents the poling process and reduces the piezoelectric strain constant. The tailoring of microstructure to achieve a high performance piezoelectric/piezomagnetic composite is proposed based on the analysis. C 2005 Springer Science + Business Media, Inc.