MIXED CUTTING CERAMICS AND METHOD FOR MANUFACTURING CUTTING PLATES FROM MIXED CUTTING CERAMICS Russian patent published in 2023 - IPC C22C1/10 C22C29/00 B22F3/14 B22F3/24 C04B35/01 B23P15/28 

FIELD: powder metallurgy.

SUBSTANCE: cutting tools for processing hard-to-cut steels and alloys, as well as high-strength and grey cast iron on machine tools. Mixed cutting ceramics contains, wt.%: aluminium oxide - 27-30, silicon oxide SiO₂ - 27-31, tantalum carbide TaC - 9-10, titanium carbide TiC - 23-24, tungsten carbide WC - 9-10. A mixture of silicon oxide and aluminium oxide is calcined at a temperature of 1750-1760°C, subjected to fine vibrogrinding on a vibratory unit for 3.5-4.5 hours and dried. After drying, titanium carbide, tantalum carbide, tungsten carbide are introduced and mixed until they are uniformly distributed over the volume and an aqueous suspension is formed, into which deoxidizing catalyst additives are introduced in the form of magnesium oxide MgO, calcium oxide CaO, sodium oxide Na₂O, and subjected to spray drying to obtain a mixture. The resulting mixture is pressed to form a cutting plate, sintered at 3870-3950°C and subjected to short-term annealing with an exposure of 10.0-15.0 minutes at a temperature of 1650-1680°C. After annealing, machining is carried out to obtain a roughness of the faces equal to 0.06-0.08 mcm.

EFFECT: increased intergranular corrosion resistance, thermal wear resistance, ductility, impact strength and workability of plates, yield strength during hot pressing and sintering of plates, strength and hardness.

2 cl, 1 tbl