Claims
- 1. A method of producing an electromagnetic steel sheet having excellent magnetic properties, said steel sheet having a specific resistivity of about 15 μΩ·cm or more, a ratio of {100}<001> integration degree to {111}<uvw> integration degree of about 2.0 or more, and crystal grains of about 10 μm to 500 μm in diameter which comprises,a) preparing a steel slab having a composition which is adjusted such that the specific resistivity of a resulting product sheet is about 15 μΩ·cm or more, and b) subjecting said slab to hot rolling, wherein a large reduction ratio is applied to said steel slab in a final rolling stage, and wherein the finishing temperature is adjusted to about 750 to 1150° C.
- 2. The method according to claim 1, wherein said reduction ratio is about 30% or more.
- 3. The method according to claim 2, wherein said final rolling stage is conducted in 1 pass.
- 4. The method according to claim 1, wherein the total reduction ratio of the final 3 passes in said hot rolling step is about 50% or more, and wherein the reduction ratio in the final pass is about 10% or more.
- 5. The method according to any one of claims 2, 3 and 4, wherein said slab contains about 0.1 to 3.5% by weight of Si and the {100}<001> integration degree of said product sheet is about 10 or more.
- 6. The method according to any one of claims 2, 3 and 4, wherein said slab contains about 0.2 to 1.2% by weight of P, and wherein the {100}<001> integration degree of said product sheet is about 3 or more.
- 7. The method according to claim 5, wherein said slab is made from a component providing a ferrite-austenite transformation temperature of about 750 to 1150° C., and wherein the finishing hot rolling temperature is about Ar1−100 to Ar1+50° C.
- 8. The method according to claim 5, wherein said slab is made from a component which provides the slab with a ferrite single phase at about 750 to 1150° C., and wherein the finishing hot rolling temperature (°C) is higher than or equal to about 1010°+110×[Si]−5×reduction ratio of the final hot rolling pass (%).
- 9. The method according to claim 6, wherein said slab is made from a component which provides the slab with a ferrite-austenite transformation at about 750 to 1150° C., and wherein the finishing hot rolling temperature is about Ar1−100 to Ar1+50° C.
Priority Claims (3)
Number |
Date |
Country |
Kind |
9-220394 |
Aug 1997 |
JP |
|
9-244216 |
Sep 1997 |
JP |
|
9-334137 |
Dec 1997 |
JP |
|
Parent Case Info
This application is a divisional of application Ser. No. 09/134,305, filed Aug. 14, 1998, now U.S. Pat. No. 6,248,185 incorporated herein by reference.
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