Piezoelectric properties of low-temperature sintered Pb0.95Ba0.05[(Mg1/3Nb2/3)0.125Zr0.445Ti0.43]O3 ceramics with chemically-added LiBiO2 sintering aid

Low-temperature fabrication of Pb0.95Ba0.05[(Mg1/3Nb2/3)0.125Zr0.445Ti0.43]O3 (PBMNZT) ceramics was investigated, and their microstructure, ferroelectric and piezoelectric properties were examined. In order to improve the sinterability and piezoelectric properties, LiBiO2 sintering aid was uniformly added to PBMNZT powders with surface chemical modification using hydrolysis of alkoxides. PBMNZT powders without LiBiO2 could not be fully densified at sintering temperatures lower than 1100 °C. However, an addition of LiBiO2 considerably improved the sinterability of PBMNZT powders, and sintering temperature consequently decreased from 1100 to 850 °C. This may be attributable to the promotion of liquid-phase sintering. And also, 0.7 wt.% LiBiO2-added PBMNZT ceramics could be fabricated without deteriorating the piezoelectric properties in the sintering temperatures below 1000 °C. A high electromechanical coupling factor (kp) of 61.7%, as well as a large field-induced strain of ∼0.17% (40 kV/cm) was obtained for 950 °C-sintered specimens with 0.7 wt.% LiBiO2 additive.