Low temperature sintering of lead-free (Bi1/2Na1/2)TiO3-SrTiO3-BiFeO3 piezoelectric ceramics by adding excess CuO

摘要

This study examined the microstructures, crystal structures, and electrical properties of 0.01mol CuO-added (1-x)(Bi1/2Na1/2)TiO3-xSrTiO(3)-2BiFeO(3) (BNST100x-2BF, x=0.20 0.28) ceramics synthesized at two different sintering temperatures. The sintering temperature of the BNST100x-2BF ceramics could be decreased from 1175 degrees C to 1000 degrees C by adding a 0.01mol CuO excess. Low-temperature sintering led to a decrease in average grain size. The dielectrics, polarization hysteresis (P-E), switching current, and electric-field induced strain (S-E) curves changed with increasing SrTiO3 content and decreasing sintering temperature. Interestingly, the highest reduction ratio of d(33)(*) was calculated to be somewhere in between the high-temperature sintered and low-temperature sintered BNST26-2BF ceramics. These results were attributed to the difference in the stabilized relaxor state and closely related to the electric field-induced reversible phase transition from the relaxor and ferroelectrics.