The Investigation Of Sb-,Li-, Composite Replaced PZT Binary System

temperature and better piezoelectric properties. Li2CO3 having a low meltingtemperature, is always doped in PZT by many researchers to lower the sinteringtemperature. But the addition of Li2CO3 always makes piezoelectric propertiesdeteriorated. The previous work of our lab, the addition of Li2CO3 and Sb2O3 in PZTSystem had been studied. The result shows not too satisfied. Different from theprevious methods, in this work we co-doped the Sb and Li in the B site of theperovskite structure. It is expected to obtain a soft type PZT with high piezoelectricconstant （d33）, high electromechanical coupling coefficient （kp） and high curietemperature （Tc）. In this work, we used the mix-oxide method to get the PZT powder.In the work, we changed the content of (Sb_3/4Li_1/4), the Zr/Ti ratio and the sinteringtemperature. After that we studied the effect on the properties of PZT with differentpoling conditions and the effect of Pb content on the properties of PZT. In the end, wedesigned a type of piezoelectric sensor using the (Sb_3/4Li_1/4)co-doped PZT materials.In order to find out the reason of the component failure, temperature shock test wascarried out.The result showed that the piezoelectric properties showed optimum values as thePb0.95Ba0.04（Zr0.52Ti0.48）0.98(Sb_3/4Li_1/4)0.02 ceramics sintered at 1200℃, and poled in thesilicon oil at 120℃by DC field at 3kV/mm for 15min. The piezoelectric constant（d33）, the dielectric constant ,the electromechanical coefficient （kp） and the curietemperature were 520pC/N, 2300, 0.81 and 290℃respectively. At the end of mywork, the effect of quieter material on the aftershock and sensitivity of the ultrasonicsensor was studied. The result showed that the aftershock and sensitivity were greatlyinfluenced by the elasticity of the quieter material. In addition, the matchingcharacteristics of thermal expansion coefficient among the quieter material,piezoelectric ceramic and aluminum alloy, was greatly affect the stability of theaftershock and sensitivity after temperature shock. The mismatching of the thermalexpansion coefficient among the quieter material, piezoelectric ceramic and aluminumalloy led to the depolarization of the piezoelectric ceramic.