METHOD OF ALLOYING SURFACE OF CASTINGS FROM IRON-CARBON ALLOYS WITH CHROMIUM BORIDES Russian patent published in 2020 - IPC B22C9/04 B22D27/18 

FIELD: foundry.

SUBSTANCE: invention relates to foundry. Method of making a gasified casting model for casting iron-carbon alloys with chromium-doped borides involves depositing a layer of an alloying composition on the surface of a foam polystyrene model. Alloying composition is prepared by mixing the powdered mixture with an adhesive binder, the content of which does not exceed 90 % of the weight of the powder mixture, wherein the powdery mixture consists of chromium and ferroboron with boron content of not less than 6 wt. %, taken with respect to the weight of chromium to the ferroboron mass from 0.08 to 0.3. Powder composition can additionally contain powders of metals, powders of alloys, ceramic powders in the form of oxides, nitrides, borides, carbides or silicides or a combination of powders of metals and said ceramic powders in an amount of not more than 60 % of the weight of the initial powdered mixture of chromium and ferroboron, which increases wear resistance of the cast alloy layer.

EFFECT: alloying composition materials enable SHS reaction during shaping of casting, which enables to obtain doped layer with high hardness, preset thickness and composition of castings from iron-carbon alloys.

6 cl, 3 ex