SINGLE CRYSTAL BETA-SIC GRAIN-MIXED ZIRCONIA-BASED SINTERED COMPACT

摘要

PURPOSE:To obtain the subject sintered compact having excellent flexual strength, fracture toughness value, and thermal durability by mixing the spherical SiC grains of a beta-type single crystal with a zirconia-based sintered compact in a specified ratio to keep the content of a tetragonal crystal in the zirconia phase in the sintered compact at a high value. CONSTITUTION:The spherical SiC grains of the beta-type single crystal having 2-10mu diameter are added to the zirconia powder added, as required, with =1 kind of sintering aid selected from the oxides of Sc, Y, and rare-earth elements in a specified ratio, and mixed. The mixture is compacted, and sintered to obtain the subject sintered compact mixed with 10.0-25.0vol.% of the single crystal beta-SiC grains having 2-10mu diameter, having a structure wherein a SiC grain 1 is present between zirconia grains 4, and wherein the content of the tetragonal zirconia in the zirconia phase in the sintered compact is controlled to =95vol.% and that of the monoclinic zirconia to =5vol.%.