METHOD OF INCREASING CORROSION RESISTANCE OF GRANULAR FERROSILICON Russian patent published in 2019 - IPC C23C8/48 C23C8/24 C22F1/02 

FIELD: metallurgy.

SUBSTANCE: invention relates to enrichment and can be used in production of ferroalloys, particularly ferrosilicon, and in shops using ferrosilicon. Method of preparation of granulated ferrosilicon to heavy-medium separation involves formation on the surface of granulated ferrosilicon protective film by action of reducing passivating medium. Reducing passivating medium used is a nitrogen-containing plasma medium of a gas mixture containing nitrogen, hydrogen and methane, at temperature of 500–590 °C for 1.5–6 hours.

EFFECT: higher corrosion resistance of granulated ferrosilicon, reinforcement of bonds between fused particles of magnetite and silicon, which increases mechanical corrosion resistance and mechanical strength of treated ferrosilicon granules.

1 cl, 1 tbl