FIELD: metallurgy, namely production of refractory nickel-base alloys, possibly used for melting carbon-free corrosion-proof refractory alloys for casting vanes of stationary power generating and gas pumping gas-turbine plants and other parts of monocrystalline structure.
SUBSTANCE: method comprises steps of melting in vacuum cleaned charge materials; decarbonization refining at adding oxidizing agent in inert-gas atmosphere; then adding in vacuum chrome, active alloying elements, rare-earth metal; refining by means of calcium. After decarbonization refining up to 40 mass% of waste casting refractory alloys are added. Refining by means of calcium is realized by adding calcium in the form of master alloy Ni-Ca during three stages: first after adding charge materials; second before chrome adding and third refining stage is combined with addition of rare-earth metal. At first and third refining stages calcium is added in quantity consisting of 0.005 - 0.010 % of melt mass. At second refining stage calcium is added in quantity determined according to given formula: Kca = n(Kcr x Km)/Mca where Kca - quantity of calcium added to melt; n - dimensionless proportionality coefficient equal to 0.002; Km -quantity of melt alloy; Kcr -quantity of chrome added to melt; Mca - calcium content in master alloy nickel - calcium. Method provides increased by 1.5 heat-resistance value of alloy, desired chrome content due to lowered till 0.001% and less oxygen content of alloy allows use up to 40 mass% of waste casting materials for melting.
EFFECT: lowered chrome losses for oxidation at melting alloys, possibility for achieving desired chrome content in ready metal due to reduced content of oxygen in alloy, enhanced heat resistance of alloy at keeping content of sulfur, nitrogen and carbon in it, improved operational reliability of stationary gas turbine plants, increased useful life period of such plants.
3 cl, 1 tbl, 1 ex
| Title | Year | Author | Number |
|---|---|---|---|
| METHOD OF FABRICATION CASTABLE REFRACTORY NICKEL-BASED ALLOYS (VERSIONS) | 2013 |
|
RU2541330C1 |
| METHOD OF PRODUCTION OF CAST HEAT RESISTANT ALLOYS ON NICKEL BASE (VERSIONS) | 2007 |
|
RU2344186C2 |
| METHOD OF MANUFACTURE OF NICKEL-BASED HIGH-TEMPERATURE ALLOYS (OPTIONS) | 2017 |
|
RU2682266C1 |
| PRODUCTION METHOD OF CARBON-FREE FOUNDRY HEAT-RESISTANT NICKEL-BASED ALLOYS | 2019 |
|
RU2696625C1 |
| METHOD OF PRODUCTION OF THE CARBON-FREE CASTING HIGH-TEMPERATURE ALLOYS | 2004 |
|
RU2274671C1 |
| METHOD OF PRODUCTION OF CARBON-FREE CASTABLE HIGH-TEMPERATURE ALLOYS ON NICKEL BASE | 2004 |
|
RU2278902C1 |
| METHOD OF HEAT-RESISTANT NICKEL-BASED CAST ALLOY OBTAINMENT | 2009 |
|
RU2392338C1 |
| METHOD OF PRODUCTION OF CARBON-FREE FOUNDRY HEAT RESISTING NICKEL-BASED ALLOYS | 2014 |
|
RU2563403C1 |
| METHOD OF PRODUCTION OF CAST HIGH-TEMPERATURE ALLOYS ON NICKEL BASE | 1988 |
|
SU1584404A1 |
| NICKEL-BASED CASTING HEAT-RESISTANT ALLOYS PRODUCTION METHOD | 2019 |
|
RU2696999C1 |
