| 摘要 |
PURPOSE:To readily and stably obtain a piezoelectric ceramic having excellent durability to driving by adding a specific amount of lanthanum element when PbTiO3-PbZrO3 based piezoelectric ceramic is produced. CONSTITUTION:Powder containing each powder of PbO, TiO3 and ZrO2 at prescribed ratio is mixed together with water by a ball mill and dehydrated, dried and calcined to afford powdery raw material. The powder is again charged in the ball mill and a prescribed amount of La2O3 powder is added to the powder and these components are mixed in wet state and dehydrated and dried to give a PZT powdery raw material. A binder is added to the raw material to granulate the raw material and the granulate is formed to afford a formed product. The forming is carried out so that 1-5mol% tantalum is contained in 100mol% total amount of lead element in the formed body, which body is heated and retained and sintered in a density lower than ideal density to provide a primary sintered compact. The sintered compact is subjected to HIP treatment which is sintered under high temperature and high pressure and the resultant sintered compact is subjected to after-processing. By the method, grain diameter of the primary sintered compact can be minimized to provide the objective piezoelectric ceramic. |
