US3933024A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for cold rolling of a high magnetic flux density grain-oriented electrical steel sheet or strip having excellent properties
Assignee: Nippon Steel Corp
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Filing: 1974-06-10
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Granted: 1976-01-20
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Expires: 1994-06-10
Abstract
Abstract A cold rolling method for producing a high magnetic flux density grain oriented electrical steel sheet or strip having remarkably excellent B8 characteristics, comprising subjecting a hot rolled steel sheet or strip a combination of heavy cold rolling with annealing during which the steel sheet or strip is held at a temperature between 100 DEG and 350 DEG C at an interim sheet thickness stage during the heavy cold rolling.
Inventors
- 👤 Fumio Matsumoto
- 👤 Katuro Kuroki
- 👤 Kunihide Takashima
- 👤 Toshihiko Takata
- 👤 Hiromichi Yasumoto
- 👤 Kuniyasu Honda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:02
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/12; C21D8/1244; C21D8/1266; C21D8/1216; C21D8/1233
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
166 words
In a cold rolling method for producing a high magnetic flux density grain oriented electrical steel sheet or strip comprising the steps of hot rolling a silicon steel material containing 2.5 to 4.0% Si, not more than 0.085% carbon and 0.010 to 0.065% acid soluble Al, annealing the hot rolled steel sheet at a temperature between 950° and 1200°C and rapidly cooling the steel sheet to precipitate AlN, subjecting the steel sheet to a one-step heavy cold rolling at a reduction rate between 81 and 95 percent to obtain a final sheet thickness, decarburization annealing of the cold rolled steel sheet, and final annealing, the improvement which comprises obtaining the final steel sheet or strip thickness by a plurality of rolling passes of the heavy cold rolling through various interim sheet thicknesses and holding the steel sheet at a temperature between 100° and 350°C for at least 1 minute during the heavy cold rolling step at least one time between the above plurality of rolling passes.
Claim 2
Dependent Claim
166 words
In a cold rolling method for producing a high magnetic flux density grain oriented electrical steel sheet or strip comprising the steps of hot rolling a silicon steel material containing 2.5 to 4.0% Si, not more than 0.085% carbon and 0.010 to 0.065% acid soluble Al, annealing the hot rolled steel sheet at a temperature between 950° and 1200°C and rapidly cooling the steel sheet to precipitate AlN, subjecting the steel sheet to a one-step heavy cold rolling at a reduction rate between 81 and 95 percent to obtain a final sheet thickness, decarburization annealing of the cold rolled steel sheet, and final annealing, the improvement which comprises obtaining the final steel sheet or strip thickness by a plurality of rolling passes of the heavy cold rolling through various interim sheet thicknesses and holding the steel sheet at a temperature between 100° and 350°C for at least 1 minute during the heavy cold rolling step at least one time between the above plurality of rolling passes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |