Abstract
The preparation of low-cost multilayer piezoelectric devices requires using cheap internal electrodes between the dielectric layers. A general strategy is to reduce the sintering temperature T(s) of the ceramic layer by sintering aids which can form a liquid phase. Here, 0.2 wt% Li(2)CO(3) was added as a sintering aid to tailor the sinterability and piezoelectricity of the commercial PZT ceramics. As verified from experiments, the piezoelectric ceramics could be densified at a sintering temperature above 940 °C, suitable for co-firing with the cheap internal electrode. The optimized sintering temperature of 980 °C can be confirmed for the 0.2 wt% Li(2)CO(3)-modified PZT ceramics due to its high piezoelectric coefficient d(33) ~ 701 pC/N, planar coupling factor k(p) ~ 66.7%, and a low mechanical quality factor Q(m) ~ 71 with a transition temperature of T(c) ~ 226 °C, presenting the characteristics of typical soft piezoelectric ceramics. Moreover, both the potential piezoelectric strain ~0.13% under 20 kV/cm and the good cycling fatigue characteristic (>10(4) cycles) of the studied piezo compositions indicates strong competitiveness in the field of multilayer piezoelectric devices.