Pzt Ceramics And Its Application Research In The Piezoelectric Transformer

Discovery of PZT ceramics is an important turning point during the develop ment process of piezoelectric ceramics. Because of its eminent piezoelectric ability, it can be widely used to manufacture piezoelectric devices, such as speaker, sensor. Th e paper mainly introduce its application on the piezoelectric transformer. Comparing wit h conventional electromagnetical transformer, piezoelectric transformer has many adva ntages, such as compact volume, high set-up ratio and non-electromagnetical pollut ion. It is very important to elect piezoelectric ceramics, when made a piezoelectric transformer.The thesis researched the property of PZT ceramics. The effect of temperature and doping on the ceramics was researched. The changes of properties were analysed under different temperature and doping condition. Meanwhile, microstructure of PZT ceramics were researched by SEM.The results showed as follow:(1)Piezoelectric ceramic display good combination properties under the temperature of1200℃.εr=1600, tanδ=1.7%, Kp=0.59, Qm=2746, d33=430pC/N.(2)The electromechanical properties of ceramic turned better,but the piezoelectric ability decreased with Mn2+doped. When the proportion of Mn2+is0.5wt%,the PZT ceramic can be sintered to density. Its volume density is7.8g?cm-3,and it has good properties. εr=2176, tan8=1.5%, d33=243pC/N, Kp=0.38, Qm=3742.(3)The piezoelectric property has increased, when In3+were doped into the PZT ceramics. When the proportion of In3+is0.6wt%, the PZT ceramics performanced well, its volume density is7.563g?cm-3. d33=440pC/N,εr=1362, tanδ=1.52%, Kp=0.658, Qm=3269.The paper also introduced how to make a kind of radial vibration piezoelectric transformer, meanwhile simulate its properties using the Mathcad soft. Then, test its empty set-up ratio and output power. The results showed that this kind of transformer needs to change and improve. The empty load set-up ratio is nearly5; output power and convert efficiency can reach as high as5.5W and80%, input square wave of17V and load resistance of2000Q. It can not be used to high power device.