EXOTHERMIC MIXTURE FOR HEAT INSULATION OF THE HEAD PART OF THE INGOT DURING CASTING OF STEELS AND ALLOYS Russian patent published in 2022 - IPC B22D7/10 

FIELD: metallurgy.

SUBSTANCE: nvention relates to the field of metallurgy. The exothermic mixture for insulating the head part of the ingot during casting of steels and alloys contains, wt.%: aluminum-containing material - 25-30, material expanding when heated - 5-15, foundry graphite - 3-5, fluorite concentrate - 2-5, calcined forging scale - 5-10, potassium nitrate, or sodium, or barium - 3-5, sawdust - 5-15 and aluminous cement - the rest. The introduction of aluminous cement contributes to the formation of a strong heat-insulating layer on the surface of the ingot. Wood chips help ignite and control the burning rate of the mixture. The gases formed during their combustion form pores in the mixture, loosen it, preventing sintering, reduce thermal conductivity and provide oxygen access deep into the mixture layer, supporting the combustion of other combustible components. Scale promotes long-term combustion of the mixture without pyroeffect, and its particles have reinforcing properties that increase the strength of the cinder.

EFFECT: obtaining a dense structure of the upper part of the resulting ingot and reducing the loss of metal with the head trim.

1 cl, 2 tbl