US3865635A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making tubes and similar products of a zirconium alloy
Assignee: Sandvik AB
•
Filing: 1973-09-04
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Granted: 1975-02-11
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Expires: 1993-09-04
Abstract
Abstract The creep strength of a tube formed from a "Zircaloy" material is improved by prefacing the final cold working step of the manufacturing procedure by heating the material to the beta -range and then cooling to room temperature.
Inventors
- 👤 Ake Sixten Boris Hofvenstam
- 👤 Erik Thomas Andersson
- 👤 Olof Krister Kallstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:00
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/186; Y; Y10; Y10S; Y10S376/00; Y10S376/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
98 words
IN A METHOD OF MAKING TUBES AND OTHER PRODUCTS WITH IMPROVED CREEP STRENGTH FROM A ZIRCONIUM ALLOY CONTAINING, IN WT. PERCENT, 1.2-1.7 SN, 0.07-0.24 FE, 0.05-0.15 CR, 00.08 NI, 0.09-0.16 O, SAID MATERIAL HAVING B-PHASE RESPECTIVELY A-PHASE STRUCTURE AT HIGH RESPECTIVELY LOW TEMPERATURES, THE TUBE OR CORRESPONDING PRODUCT BEING PLASTICALLY WORKED TO FINAL DIMENSION BY MEANS OF HOT AND COLD WORKING, IN WHICH THE COLD WORKING INCLUDES SEVERAL STEPS WITH INTERMEDIATE RECRYSTALLIZATION ANNEALINGS, THE IMPRIVED PROCEDURE WHICH CONSISTS IN HEATING THE MATERIAL, BEFORE THE LEAST COLD WORKING STEP, TO THE B-RANGE AND THEN COOLING IT TO ROOM TEMPERATURE.
Claim 2
Dependent Claim
98 words
IN A METHOD OF MAKING TUBES AND OTHER PRODUCTS WITH IMPROVED CREEP STRENGTH FROM A ZIRCONIUM ALLOY CONTAINING, IN WT. PERCENT, 1.2-1.7 SN, 0.07-0.24 FE, 0.05-0.15 CR, 00.08 NI, 0.09-0.16 O, SAID MATERIAL HAVING B-PHASE RESPECTIVELY A-PHASE STRUCTURE AT HIGH RESPECTIVELY LOW TEMPERATURES, THE TUBE OR CORRESPONDING PRODUCT BEING PLASTICALLY WORKED TO FINAL DIMENSION BY MEANS OF HOT AND COLD WORKING, IN WHICH THE COLD WORKING INCLUDES SEVERAL STEPS WITH INTERMEDIATE RECRYSTALLIZATION ANNEALINGS, THE IMPRIVED PROCEDURE WHICH CONSISTS IN HEATING THE MATERIAL, BEFORE THE LEAST COLD WORKING STEP, TO THE B-RANGE AND THEN COOLING IT TO ROOM TEMPERATURE.
Claim 3
Dependent Claim
33 words
Method according to claim 1, wherein before the last cold working step the material is heated to a temperature between 860* - 1,250* C. and preferably to a temperature between 1,000* -1,150* C.
Claim 4
Dependent Claim
34 words
Method according to claim 1, wherein the material after the last cold working step is annealed in the temperature range 400* - 700* C. and preferably in the temperature range 500* - 530* C.
Claim 5
Dependent Claim
23 words
Method according to claim 1, wherein the cross-sectional area of material in the last cold working step is reduced at least 50 percent.
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) | 1978-02-10 | 1978-08-12 | 1979-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-10 | 1982-08-12 | 1983-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-10 | 1986-08-12 | 1987-02-11 | $7700.00 | Window Closed / Lapsed |