METHOD FOR SYNTHESIZING PIEZOELECTRIC AND DIELECTRIC CERAMICS POWDER

摘要

PURPOSE:To enable synthesis of a perovskite type oxide powder containing a group Va element which has been difficult to produce in a fine and homogeneous form, by precipitating hydroxide of the group Va element in coprecipitates of component elements other than the group Va element formed with oxalic acid, drying and calcining the resultant mixed precipitates. CONSTITUTION:A solution containing (A) ions of one or more elements, such as Pb, Bi or Ba, and (B) ions of one ore more elements, such as Mg, Cr or Zn, so as to provide a composition ratio of a substance to be synthesized is dripped into an alcoholic solution of oxalic acid to form coprecipitates of oxalates of the ions (A) and (B). Aqueous ammonia is then added to the solution while stirring to adjust the pH to =3-=13. A solution containing ions of a group Va element is subsequently dripped to the above-mentioned precipitates at the adjusted pH as described above to precipitate hydroxide of the group Va element. The resultant mixed preipitates are then filtered, washed with an alcohol, dried by heating, calcined and thermally decomposed to afford the aimed perovskite type ceramics powder.