Outer-layer material for hot-rolling roll, and hot-rolling composite roll
AssigneeJfe Steel Corporation
InventorsKenji Ichino, Tetsuo Mochida, Hiromitsu Shibata
Life of this patent
Estimating the term…
Abstract
A surface layer material of a hot rolling mill roll is provided. The surface layer has a chemical composition containing, by mass %, C: 2.4% or more and 3.5% or less, Si: 1.2% or more and 2.4% or less, Mn: 0.2% or more and 2.0% or less, Cr: 0.8% or more and 2.1% or less, Mo: 0.3% or more and 1.1% or less, Ni: 3.0% or more and 6.0% or less, V: 1.0% or more and 2.2% or less, Nb: 0.1% or more and 0.5% or less, REM: 0.0005%) or more and 0.1% or less, Al: 0.003% or more and 0.05% or less, and the balance being Fe and inevitable impurities. The contents of C, Cr, V, Nb, REM, and Al satisfy the relationships Cr+0.2≦C−(0.24×V+0.13×Nb)≦3.0 and 0.01≦REM/Al≦3.2.
Claims16
A surface layer material of a hot rolling mill roll which is adapted to be used for a surface layer of a hot rolling mill composite roll, the material having a chemical composition containing, by mass%, C:
- 2.4% or more and 3.5% or less, Si:
- 1.2% or more and 2.4% or less, Mn:
- 0.2% or more and 2.0% or less, Cr:
- 0.8% or more and 2.1% or less, Mo:
- 0.3% or more and 1.1% or less, Ni:
- 3.0% or more and 7.0% or less, V:
- 1.2% or more and 2.2% or less, Nb:
- 0.1% or more and 0.8% or less, REM:
- 0.0005% or more and 0.1% or less, Al:
- 0.003% or more and 0.05% or less, and the balance being Fe and inevitable impurities, wherein the contents of C, Cr, V, Nb, REM, and Al satisfy relational expressions (1) and (2) below:
- Cr+0.2≦C−(0.24×V+0.13×Nb)≦3.0 (1)
- 0.01≦REM/Al≦3.2 (2),
- where C, Cr, V, Nb, REM, and Al respectively represent the mass% contents of the corresponding chemical elements.
A hot rolling mill composite roll comprising:
- an inner layer, and
- a surface layer welded and, integrated with the inner layer,
- the surface layer having a chemical composition containing, by mass%, C:
- 2.4% or more and 3.5% or less, Si:
- 1.2% or more and 2.4% or less, Mn:
- 0.2% or more and 2.0% or less, Cr:
- 0.8% or more and 2.1% or less, Mo:
- 0.3% or more and 1.1% or less, Ni:
- 3.0% or more and 7.0% or less, V:
- 1.2% or more and 2.2% or less, Nb:
- 0.1% or more and 0.8% or less, REM:
- 0.0005% or more and 0.1% or less, Al:
- 0.003% or more and 0.05% or less, and the balance being Fe and inevitable impurities,
- wherein the contents of C, Cr, V, Nb, REM, and Al satisfy relational expressions (1) and (2) below:
- Cr+0.2 ≦C−(0.24×V+0.13×Nb)≦3.0 (1)
- 0.01 ≦REM/Al≦3.2 (2),
- where C, Cr, V, Nb, REM, and Al respectively represent the mass% contents of corresponding chemical elements.
Dependencies are inferred from the claim text.