IRON-BASED INVAR ALLOY Russian patent published in 2024 - IPC C22C38/10 C22C38/08 C22C38/04 C22C38/02 C22C30/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to foundry production of invar alloys based on iron with minimum temperature coefficient of linear expansion. Iron-based alloy is configured to form articles with a structure without carbide phases and martensite and contains nickel, cobalt, carbon, silicon, manganese, calcium and unavoidable impurities, including oxygen, sulfur, phosphorus, nitrogen, hydrogen, with the following ratio of components, wt.%: nickel 32.0–35.0, cobalt 3.6–6.0, carbon 0.75–1.5, silicon 0.1–0.5, manganese 0.1–0.4, calcium 0.001–0.1, iron and unavoidable impurities—the rest. Following conditions are simultaneously satisfied for the alloy composition: Ni/Co=6–8 and (Ni+Co)/C=30–50, where: Ni—nickel content, wt.%, Co—cobalt content, wt.%, C—carbon content, wt.%.

EFFECT: improved fluidity properties while maintaining minimum temperature coefficient of linear expansion in the temperature range from minus 60 °C to 200 °C.

1 cl, 1 dwg, 2 tbl