| 摘要 |
PURPOSE:To improve electromechanical coupling coefficient, permittivity, other piezoelectric characteristic of a piezoelectric porcelain by mixing two or more types of lead titanate-zirconate and piezoelectric porcelain material made of other metal oxide except lead oxide, first temporarily baking the mixture, then adding remaining component, second temporarily baking it, the molding and baking it. CONSTITUTION:Piezoelectric porcelain is formed of PbTiO3-PbZrO3-Me (where Me=at least one of PbO, Nb2O5, MnO, Sb2O5, SnO, Bi2O3, MgO, W2O5, Fe2O3, Cr2O3, NiO, CoO, ZnO, TaO, In2O3 and CuO). For example, predetermined quantities of TiO2, ZvO2, Nb2O5 are weighed, first temporarily baked at 800-1200 deg.C, and second temporarily baked at 700-1000 deg.C. Further, the lead oxide of the components of 1.8-2.3wt. times as large as the whole weight of the components except the lead oxide by converting it to that corresponding to Pb3O4 is added. If it is added less than this, its sintering characteristic is deteriorated, and its piezoelectric characteristic is reduced. Then, the obtained temporarily baked material is molded in a disc shape, and baked at 1100-1200 deg.C. Even if its baking temperature is varied, its piezoelectric characteristic is not largely varied, and the temperature management of the baking step is facilitated. |
