Patent US5228949A successfully refreshed from Google Patents.
US3660174A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method in the manufacture of stainless, hardenable chromium-steel strip and sheet
Assignee: Uddeholms AB
•
Filing: 1969-05-23
•
Granted: 1972-05-02
•
Expires: 1989-05-23
Abstract
Abstract There is provided a method of producing stainless, chromiumsteel sheet or strip having a high resistance to corrosion and an improved hardness, and which has a relatively high yield point / ultimate strength ratio in an unhardened state, the starting material used in the method being one of substantially a pearlite structure and in which the material is heated and worked at specific temperatures so as to break down the pearlite structure and transform said structure to one comprising finely-divided spheroidized carbides in a ferritic matrix.
Inventors
- 👤 Klas-Erik Jakenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:03
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
19 words
A method according to claim 1, wherein the hot-rolled material is cooled to room temperature in an insulating medium.
Claim 2
Dependent Claim
37 words
A method according to claim 1, in which the steel is a stainless, hardenable chromium steel in which rolling of the material with the pearlitic structure is effected in the temperature range from 700* to 780* C.
Claim 3
Dependent Claim
20 words
A method according to claim 1, characterized in that the steel is rolled at a temperature of about 700* C.
Claim 4
Dependent Claim
45 words
As a new product, hardenable steel strip or sheet containing finely divided spheroidized carbide particles in a ferritic matrix having in excess of 40 such particles per 100 Mu m2, said steel strip or sheet having been manufactured by the method defined in claim 1.
Claim 5
Dependent Claim
87 words
A steel strip or sheet according to claim 5, characterized in that the steel matrix has an alloying composition essentially consisting of from 0.2 to 1.5 weight-percent carbon, 5 to 20 weight-percent chromium, 0 to 4 weight-percent of an alloying metal selected from the group consisting of Ni, Mo, Mn, Cu and Co, 0 to 3 weight-percent of an alloying element of the group consisting of W and Si, 0 to 2 weight-percent of V, and 0 to 1 weight-percent of Ti, Ta, Nb, B and Be.
References Cited (Backward Citations)
US2801916A
Cited
US2905577A
Cited
US3116180A
Cited
US3216868A
Cited
US3281287A
Cited
US3425877A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |