| 摘要 |
PURPOSE:To obtain a high-strength ceramic calcined compact having a high toughness by passing a formed body prepared by mixing a powdery ceramic raw material with a binder and sintering assistant through a specific dipping step and then sintering the resultant formed body. CONSTITUTION:A formed body prepared by mixing a powdery raw material with a binder and sintering assistant is sintered to provide a ceramic sintered compact. In the process, the following steps are carried out. That is the first step for dipping the aforementioned formed body of a calcined compact obtained by calcining the aforementioned formed body in a solution capable of dissolving an additive and the second step for dipping the abovementioned formed body or calcined compact in a solution containing soluble metal salts dissolved therein. Parts with a high concentration of the additive, such as the sintering assistant, are diluted by the aforementioned first step and parts with a low concentration are conversely increased to homogenize the whole. The grain growth rate is equalized in sintering to suppress disadvantages, such as abnormal grain growth, etc. Furthermore, the impregnated substance in the solvent can be deposited in the form of a metal or the metal surface converted into a ceramic in grain boundaries and voids in vicinity thereof after sintering by the second step and stress relaxation is promoted to enhance the toughness thereof. |
