METHOD OF PRODUCING ANTIFRICTION SPHERULITIC IRON Russian patent published in 2003 - IPC

FIELD: metallurgy, particularly, production of antifriction spherulitic irons. SUBSTANCE: method includes smelting of pig iron and treatment of its melt in casing ladle with inoculating mixture of components containing ground alloying composition and steel wastes. Produced pig iron contains, %: manganese, 0.7; chromium, up to 0.05; and sulfur, up to 0.08. Pig iron is treated with inoculating mixture of components additionally containing silicobarium, tin, copper wastes, pig iron wastes and fluorspar with the following ratio of components, mas.%: alloying composition, 33-37; silicobarium, 4.5-6.0; tin, 1.8-2.2; steel and pig iron wastes, 20-25; fluorspar, 10-12; total quality of mixture amounts up to 4.5-6 mas.% of iron, and alloying composition contains silicon, magnesium, calcium, rare-earth metals, copper, aluminum and iron in the following ratio of components, mas.%: silicon, 18032; magnesium, 4-9; calcium, 3-8; rare-earth metals, 3.5-10; copper, 27-50; aluminum, 1-3; iron, the balance. Alloying composition is ground to obtain fraction sizing less than 3 mm. Invention provides for increasing of stability of inoculation process and stabilization of iron hardness in castings, reduction of pyroeffect in inoculation, increase of magnesium assimilation, degree of graphite spheroidization and improved structure of iron in castings. EFFECT: higher efficiency. 2 cl, 3 tbl