Method of producing cubic boron nitride-based polycrystalline material. RU patent 2449831.

FIELD: process engineering.

SUBSTANCE: invention relates to producing cubic boron nitride-based polycrystalline material. Proposed method comprises subjecting charge containing composite powder BNr+AIN with grain size of 4-100 nm obtained in SAA-process from boron-aluminium-nitrogen-containing compounds, cubic boron nitride and catalyst, to high pressure and temperature, at the following ratio of components, in wt %: BNr+AIN - 65-75, cubic BNr - 15-25, catalyst - 3-10. Ratio of hexagonal boron nitride to aluminium nitride in composite powder makes (4-6):1.Grain size of cubic boron nitride powder may make 1-40 mcm. Additionally, powder of hexagonal boron nitride with grain size of 1-40 mcm in amount of 1-15% wt % or silicon in amount of 0.1-1 wt % may be added to said charge. Synthesis is conducted at 60-120 kbar and 1700-2400°C for 15-60 s.

EFFECT: higher wear resistance.

5 cl, 1 tbl

IPC classes for russian patent Method of producing cubic boron nitride-based polycrystalline material. RU patent 2449831. (RU 2449831):

C30B28 - Production of homogeneous polycrystalline material with defined structure

C04B35/5831 -

B01J3/06 - Processes using ultra-high pressure, e.g. for the formation of diamonds; Apparatus therefor, e.g. moulds, dies (B01J0003040000 takes precedence;presses in general B30B)

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