ZrO2-Al2O3 based ceramic granules with cellulose nanofibers, manufacturing method of the granulated material, calcined powder using the granulated material and its manufacturing method, ceramic sintered body using the calcined powder and Its manufacturing method

摘要

PROBLEM TO BE SOLVED: To provide a ZrO2-Al2O3 ceramic sintered body having high density and high mechanical properties, and a method for producing the same. SOLUTION: Using Zr salt, Y salt and Al salt, the molar ratio of ZrO2 and Y2O3 is 97.0: 3.0 to 98.0: 2.0, and the molar ratio of Y2O3 added ZrO2 and Al2O3 is 80:20 to 70:30. Zr, Y, Al are co-precipitated to prepare ZrO2 (Y2O3) -Al2O3 neutralized co-precipitated uncalcined powder (step A). ), Prepare a cellulose nanofiber (CNF) aqueous dispersion having a specific viscosity (step B), and add the CNF aqueous dispersion so that the CNF is 0.12 to 0.20 parts by mass with respect to 100 parts by mass of the powder. After mixing, the granules are processed into granules (step C), and the obtained granules are heat-treated at 650 to 750 ° C. for 7 to 12 hours, and further calcined at 800 to 950 ° C. for 0.5 to 3 hours. To prepare a calcined powder (step D). High-strength ceramics can be produced by pressure-molding this calcined powder and sintering it in the air, or by mixing it with c-BN powder or ZrC powder and then molding and sintering it. [Selection diagram] None