| 摘要 |
PURPOSE:To obtain a sinter-molded article having high strength and improved flexural strength by charging aluminum oxide powder, zirconium oxide powder, water and a deflocculant to a crushing mixer, stopping the mixing after carrying out a specific operation, pouring the mixture into a casting mold and sintering the formed product. CONSTITUTION:Water and a deflocculant are charged to a crushing mixer and then specific amounts of aluminum oxide powder and zirconium oxide powder are charged to the mixer while driving the mixer at a low speed. The operation is charged to high-speed operation mode to apply grinding and kneading actions on the mixture and the operation is stopped when the curve obtained by plotting the slurry viscosity in the mixer versus time reaches the lowest point. The slurry is poured into a casting mold prepared beforehand and the formed slurry is sintered to obtain the objective sinter-molded article. The slurry dispersed in stable low viscosity state can be cast-molded in high precision to enable the suppression of the scattering of backing shrinkage within + or -0.1%. Accordingly, the crack generation can be prevented and the yield of product can be improved. A slurry exhibiting thixotropic nature gives extremely high speed of building in cast-molding process, however, cracks frequently occur in the drying and baking of the formed article and the shrinkage is remarkably scattered to cause the lowering of the yield of product. |
