FOUNDRY INVAR ALLOY BASED ON IRON Russian patent published in 2021 - IPC C22C38/52 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to the foundry production of invar alloys with a minimum temperature coefficient of linear expansion (TCLE), and can be used for the manufacture of equipment, including large-sized ones, used in the production of products made of composite materials (PCM materials), in particular from carbon composites. The foundry invar alloy based on iron contains, by wt. %: nickel (Ni) 32.0-34.5, cobalt (Co) 2.0-3.5, carbon (C) 0.75-1.5, copper (Cu) 0.12 – 0.25, silicon (Si) 0.18-0.28, manganese (Mn) 0.01-no more than 0.3, at least one component selected from the group of rare earth elements (REM): cerium, lanthanum and yttrium in the sum of 0.05-0.10, the rest is iron and unavoidable impurities. The following conditions are met, by wt. %: Cu + Si = 0.3-0.53, Cu / Si = 0.55-1.0, Ni + Co = 35.4-37.0, Ni / Co = 9.2-17.0, (Ni + Co) / C = 24-49.

EFFECT: alloy has a TCLE in the temperature range of 20-200° at a level not exceeding 2.5×10^-6 К^-1 with significantly improved casting properties, namely: the fluidity of the alloy is at the level of 210-230 mm according to a complex coquille U-shaped sample.

1 cl, 4 dwg