| 摘要 |
PROBLEM TO BE SOLVED: To widen the working temperature and improve the displacement characteristic when it is repeatedly used for a long period of time in the application to motor vehicles by specifying the proportion of the tetragonal crystals in the crystalline phase of the PZT piezoelectric porcelain composition. SOLUTION: As raw materials, PbO, ZrO2 and other oxides giving the third components are mixed in a proportion that the objective composition is given, calcinated, molded and fired to give a piezoelectric element. The ratio of the rhombohedral crystals to the tetragonal crystals in the composition can be varied by this component ratio. When the proportion of the tetragonal crystals is set to 83-95%, the piezoelectric element produced from this composition shows a large displacement, small current leak and high stability to the temperature change. Additionally, the actuator produced from the piezoelectric element shows small reduction in the displacement and high durability, even when it is repetitively driven. |
