Production method for maraging steel and production method for maraging steel consumable electrode
AssigneeHitachi Metals, Ltd.
InventorsTakahiko Kamimura, Yuuichi Hadano, Kenta Imazeki, Katsuhiko Ohishi
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Abstract
The invention provides a maraging steel production method in which an oxide is added during an Mg oxide formation step, the production method including: the Mg oxide formation step in which Mg is added to molten steel and MgO is formed in the molten steel, during primary melting; a consumable electrode production step in which, after the Mg oxide formation step, the molten steel is solidified and a consumable electrode having residual MgO is obtained; and a vacuum arc re-melting step in which the consumable electrode is used and vacuum arc re-melting is performed.
Claims5
A method for producing a maraging steel, comprising:
- a magnesium oxide formation step including adding an amount of magnesium into a molten steel in a primary vacuum melting process to form MgO in the molten steel;
- a consumable electrode production step including solidifying the molten steel after the magnesium oxide formation step to obtain a consumable electrode including MgO;
- and
- a vacuum arc remelting step including vacuum arc remelting with use of the consumable electrode to produce a maraging steel,
- wherein the magnesium oxide formation step includes adding an amount of an oxide having a higher standard free energy of formation than MgO;
- and
- wherein the maraging steel after the vacuum arc remelting comprises, by mass,
- not more than 0.1% of carbon;
- 0.01 to 1.7% of aluminum;
- 0.2 to 3.0% of titanium;
- 8 to 22% of nickel;
- 5 to 20% of cobalt;
- 2 to 9% of molybdenum;
- not more than 0.0030% of magnesium, and
- the balance being iron and impurities.
Dependencies are inferred from the claim text.