AL2O3-TIC-BASED SINTERED PRODUCT AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain the dense sintered product having uniform characteristics, relaxed in inner stress in one axial direction to prevent deformation on cutting, and excellent in mechanical processability by molding a raw material containing Al2 O3 as a main component and a specific amount of TiC into a prescribed shape, sintering the molded product by a hot-press method, and subsequently thermally treating the sintered product by a hot isotropic pressure pressurization method. SOLUTION: This Al2 O3 -TiC-based sintered product contains Al2 O3 as a main component and further 20-40 wt.% of TiC, and has a partial specific gravity variation of =0.02, a residual inner stress of 0.08 kgf/mm2 and a fractional toughness K of =4.3 PMa m. The method for producing the sintered product comprises molding a raw material comprising 80-60 wt. % of Al2 O3 , 20-40 wt.% of TiC and a sintering auxiliary (e.g. Yb2 O3 ) in an amount of =1 wt.% on the total amount of the Al1 O3 and the TiC into a prescribed shape, sintering the molded product at a temp. of 1,550-1,800 deg.C and at a pressure of 200-800 kg/cm2 by a hot press method, and subsequently thermally treating the sintered product at a temp. of 1,500-1,700 deg.C and at a pressure of 1,000-2,000 kgf/cm2 by a hot isotropic pressure pressurization method.