METHOD OF HEAT-RESISTANT NICKEL-BASED CAST ALLOY OBTAINMENT Russian patent published in 2010 - IPC C22C1/02 

FIELD: metallurgy.

SUBSTANCE: invention claims method of heat-resistant nickel-based cast alloy obtainment, involving melting of waste metal charge, charge refining in vacuum at melt temperature of 1500-1700°C, and addition of rare-earth metals in amount of 0.015-0.20% of the charge weight. Metal charge refining involves addition of carbon in amount of 0.001-0.05% of the charge weight, and cyclical processing of melt by heating and cooling, with heating and cooling duration ratio of (0.5-1.0):(1.0-1.5). Before rare-earth metal addition, calcium and/or magnesium are added. Metal charge consists of casting waste and/or utilised parts from heat-proof casting alloys subjected to sand-blast or bead-blast surface processing. Metal charge can be molten under inert gas pressure of 50-500 mm Hg. Calcium and/or magnesium are added at the following ratio with rare-earth metals: Q₁=(0.1-1.0)Q₂, where Q₁ is amount of calcium and/or magnesium, % of metal charge weight, Q₂ is amount of rare-earth metals, % of metal charge weight.

EFFECT: reduction of detrimental impurity content, enhanced heat resistance of alloy, increased yield in casting of blades with monocrystalline structure.

4 cl, 1 tbl, 5 ex