MANUFACTURING METHOD OF ITEMS FROM CERAMIC MATERIAL BY HOT PRESSING BASED ON SILICON NITRIDE Russian patent published in 2012 - IPC C04B35/593 

FIELD: metallurgy.

SUBSTANCE: manufacturing method of items from material on the basis of silicon nitride consists in preparation of the charge by mixing silicon nitride with additives at least of magnesium oxide and yttrium oxide, together with mechanical activation, addition to the charge of organic plasticising agent and formation of workpieces for hot pressing. Hot pressing is performed at temperature of 1600-1700°C, pressing pressure of 25-35 MPa, and exposure during 10-20 minutes. Mechanical activation is performed in planetary centrifugal mill at centrifugal acceleration 10-20 g during 10-20 minutes and ratio of the mass of balls to mass of mixture of 6:1 to 12:1; at that, balls and drum of planetary mill are made from ceramic material.

EFFECT: obtaining ceramic material with homogeneous fine-grain structure at shortening the time of the process cycle and reducing the hot pressing temperature.

3 cl, 2 ex, 4 dwg