METHOD FOR POLYCRYSTALLINE DIAMOND MATERIAL PRODUCTION Russian patent published in 1994 - IPC

FIELD: diamond material production. SUBSTANCE: diamond powder is affected by chemical purification and is treated with carbon dioxide within 25-35 min at 600-900 C. The latter process is carried out in the presence of potassium or sodium compounds (hydroxide, carbonate or bicarbonate being used), their ratio to diamond powder is 1: (6-20). Then cooling to room temperature, treating with hydrochloric acid, washing by distilled water to neutral reaction are carried out. Then treating with methane within 1-2 h at 500-600 C followed by compacting at high temperature and pressure take places. EFFECT: improves efficiency of the method. 1 tbl