US3920487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Press forming cold rolled steel sheet and a producing method thereof
Assignee: Nippon Steel Corp
•
Filing: 1973-09-21
•
Granted: 1975-11-18
•
Expires: 1993-09-21
Abstract
Abstract A cold rolled steel sheet having excellent press formability and ageing properties for auto bodies, especially improved stretchability and slow ageing properties, and a method for preparation thereof by means of a continuous annealing method.
Inventors
- 👤 Hisashi Gondo
- 👤 Hiroshi Takechi
- 👤 Mitsunobu Abe
- 👤 Norimasa Uehara
- 👤 Kunihiko Komiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:26
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/02; C21D8/04; C21D8/0447; C21D8/0473; C21D9/00; C21D9/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
41 words
A METHOD FOR PRODUCING A SLOW AGEING COLD ROLLED STEEL PLATE FOR PRESS FORMING COMPRISING HOT ROLLING A STEEL SLAB HAVING A CHEMICAL COMPOSITION COMPRISING NOT MORE THAN 0.1% CARBON AND NOT MORE THAN 0.30% MANGANESE IN WHICH 0.002.N (PPM)-0.03<K<0.17+0.002.N(PPM) WHERE.
Claim 2
Independent Claim
41 words
A METHOD FOR PRODUCING A SLOW AGEING COLD ROLLED STEEL PLATE FOR PRESS FORMING COMPRISING HOT ROLLING A STEEL SLAB HAVING A CHEMICAL COMPOSITION COMPRISING NOT MORE THAN 0.1% CARBON AND NOT MORE THAN 0.30% MANGANESE IN WHICH 0.002.N (PPM)-0.03<K<0.17+0.002.N(PPM) WHERE.
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) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |