METHOD OF PRODUCING POWDER COMPOSITION BASED ON ALUMINUM OXYCARBIDES Russian patent published in 2019 - IPC C01B32/907 C01F7/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to powder metallurgy and can be used in making hardening and alloying additives for aluminum alloys, carbon-containing refractory, ceramic and abrasive materials. First, an initial mixture of aluminum hydroxide and soot is prepared by depositing aluminum nitrate aqueous solution with aqueous ammonium solution at pH equal to 6.0–7.5 and temperature of 60–85 °C, at weight ratio of aluminum in terms of oxide and soot, equal to 1–(1.0–4.5), respectively. Then obtained hot precipitate is filtered, washed with water and dried at 100–110 °C. Dried deposit is annealed at the first stage by microwave radiation with frequency of 2,450–3,000 MHz and power of 700 W in an argon flow, which is supplied at rate of 5–6 l/h, with heating rate 20 °C/min up to 500–510 °C, heating rate 10 °C/min up to 700–710 °C and heating rate 5 °C/min up to 1,200–1,210 °C with holding at this temperature for 120–130 minutes. At second step firing is carried out at temperature 1,600–1,800 °C for 120–130 minutes in vacuum of 1.0·10^-2–9.0·10^-3 Torr.

EFFECT: obtained composition based on a mixture of aluminum oxycarbides is an ultrafine powder with average particle size of less than 500 nm and does not contain foreign impurities.

1 cl, 4 dwg, 1 tbl, 2 ex