Forged steel roll
AssigneeNippon Steel Corporation
InventorsSeiji ITO, Daisuke KASAI, Taketo MAEJIMA, Takahiko ITO, Keita KUROTSU, Hiroki FUJIWARA, Kazuya HANAORI
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Abstract
A forged steel roll according to the present disclosure has a chemical composition consisting of, in mass %, C: 0.70 to 1.50%, Si: 0.20 to 1.50%, Mn: 0.20 to 1.50%, P: 0.030% or less, S: 0.0200% or less, Al: 0.050% or less, N: 0.2000% or less, O: 0.0050% or less, Cr: 2.80 to 8.00%, Mo: 0.40 to 3.00%, Cu: 0.100% or less, B: 0.0100% or less, Ni: 0 to 1.20%, V: 0 to 2.00%, and Nb: 0 to 0.50%, with the balance being Fe and impurities. A large-angle grain boundary length per 1 mm2 in an outer layer of the forged steel roll is 2500 to 9000 mm.
Claims8
A forged steel roll, having a chemical composition consisting of, in mass %,
- C:
- 0.70 to 1.50%,
- Si:
- 0.20 to 1.50%,
- Mn:
- 0.20 to 1.50%,
- P:
- 0.030% or less,
- S:
- 0.0200% or less,
- Al:
- 0.050% or less,
- N:
- 0.2000% or less,
- O:
- 0.0050% or less,
- Cr:
- 2.80 to 8.00%,
- Mo:
- 0.40 to 3.00%,
- Cu:
- 0.100% or less,
- B:
- 0.0100% or less,
- Ni:
- 0 to 1.20%,
- V:
- 0 to 2.00%,
- Nb:
- 0 to 0.50%, and
- the balance:
- Fe and impurities,
- wherein:
- a large-angle grain boundary length per 1 mm2 in an outer layer of the forged steel roll is 2500 to 9000 mm.
Dependencies are inferred from the claim text.