METHOD OF PRODUCTION OF COMPOSITE IRON CASTINGS Russian patent published in 2003 - IPC

FIELD: foundry, relating to production of composite iron castings by special methods of casting. SUBSTANCE: method includes making of inserts from alloying composition, gluing-them in polystyrene foam pattern, making of mold and filling of mold with molten gray iron. Inserts are made of mixture with the following-amounts of components, wt.%: powdery magnesium 2-4; cryptocrystalline graphite 3-4; ferrochromium VaCr 650 or VaCr 800 2-3; polystyrene 1.5-2; the balance, ferratitanium with titanium content of 60-68%. Materials comprising insert composition provide for proceeding of self-propagating high-temperature synthesis in filling of mold with liquid iron. Reaction proceeds with liberation of large amounts of heat. EFFECT: improved conditions of formation in iron castings of wear-resistant hard-alloy surface layer and high-strength transition layer. 1 tbl