US4664727A
Expired / Lapsed
US
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Zirconium alloy having superior corrosion resistance
Assignee: Hitachi Ltd
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Filing: 1983-06-21
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Granted: 1987-05-12
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Expires: 2003-06-21
Abstract
Abstract A zirconium alloy having superior corrosion resistance, containing Sn of a small amount not less than the amount of Sn existing in the solid-solution of the zirconium alloy at a room temperature, and at least one kind of Fe and Cr each of a small amount not less than the amount of each of Fe and Cr existing in the solid-solution of the zirconium alloy at a room temperature, the zirconium alloy being annealed after the solution heat treatment at a temperature at which both the alpha phase and beta phase thereof are included in the zirconium alloy, the total amount of said at least one kind of Fe and Cr existing in the solid-solution of the zirconium alloy being not less than 0.26%.
Inventors
- 👤 Masahisa Inagaki
- 👤 Ryutaro Jinbo
- 👤 Keiichi Kuniya
- 👤 Isao Masaoka
- 👤 Hideo Maki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:04
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/186
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
171 words
A zirconium alloy having superior corrosion resistance, containing Sn of a small amount not less than the amount of Sn existing in the solid-solution of the zirconium alloy at a room temperature, and at least one element selected from the group consisting of Fe and Cr, each of a small amount not less than the amount of each of Fe and Cr both existing in the solid-solution of the zirconium alloy at a room temperature, and with or without Ni, the zirconium alloy being annealed after the solution heat treatment, the solution heat treatment being at a temperature at which both the α phase and β phase thereof are included in the zirconium alloy, the total amount of said at least one element of Fe and Cr; or said at least one element of Fe and Cr, and Ni; existing in the solid-solution of the zirconium alloy, after the final annealing, after the solution heat treatment, being not less than 0.26 weight %, whereby nodular corrosion of said alloy is prevented.
Claim 2
Dependent Claim
171 words
A zirconium alloy having superior corrosion resistance, containing Sn of a small amount not less than the amount of Sn existing in the solid-solution of the zirconium alloy at a room temperature, and at least one element selected from the group consisting of Fe and Cr, each of a small amount not less than the amount of each of Fe and Cr both existing in the solid-solution of the zirconium alloy at a room temperature, and with or without Ni, the zirconium alloy being annealed after the solution heat treatment, the solution heat treatment being at a temperature at which both the α phase and β phase thereof are included in the zirconium alloy, the total amount of said at least one element of Fe and Cr; or said at least one element of Fe and Cr, and Ni; existing in the solid-solution of the zirconium alloy, after the final annealing, after the solution heat treatment, being not less than 0.26 weight %, whereby nodular corrosion of said alloy is prevented.
Claim 3
Dependent Claim
61 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1, consisting essentially, by weight, of 1-2% Sn, at least one element selected from the group consisting of 0.05-0.3% Fe and 0.05-0.2% Cr, 0-0.1% Ni; with the proviso that when the alloy contains no Ni, Fe is contained in an amount of 0.06-0.3%; and the balance Zr and inevitable impurities.
Claim 4
Dependent Claim
54 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1 or claim 2, wherein the solution heat treatment is effected by maintaining the zirconium alloy at a temperature of 825° to 965° C. for a period of time not more than 10 minutes, then the zirconium alloy being quenched from said temperature.
Claim 5
Dependent Claim
31 words
A zirconium alloy having superior corrosion resistance as claimed in claim 3, wherein the annealing is effected at a temperature of 400°-700° C. for a period of time of 1-5 hours.
Claim 6
Dependent Claim
63 words
A zirconium alloy having superior corrosion resistance as claimed in claim 2, wherein the time and temperature of said annealing are adjusted to maintain the total amount of said at least one element of Fe and Cr; or at least one kind of Fe and Cr, and Ni; existing in the solid-solution of the zirconium alloy at not less than 0.26 weight %.
Claim 7
Dependent Claim
26 words
A zirconium alloy having superior corrosion resistance as claimed in claim 5, wherein the annealing is performed at least two times, after respective cold working steps.
Claim 8
Dependent Claim
24 words
A zirconium alloy having superior corrosion resistance as claimed in claim 6, wherein the annealing is performed three times, after respective cold working steps.
Claim 9
Dependent Claim
26 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1 or claim 7, said alloy having been formed into a nuclear fuel cladding tube.
Claim 10
Dependent Claim
27 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1 or claim 7, said alloy having been formed into a nuclear fuel assembly channel box.
Claim 11
Dependent Claim
69 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1 or claim 7, said alloy having been formed into at least one of a nuclear fuel cladding tube and a nuclear fuel assembly channel box, wherein said fuel cladding tube is adapted to hold a nuclear fuel substance, and wherein said fuel assembly channel box is adapted to integrally support a plurality of the fuel cladding tubes.
Claim 12
Dependent Claim
26 words
A zirconium alloy having superior corrosion resistance as claimed in claim 2 or claim 7, wherein Ni is contained in an amount of 0.01-0.08 weight %.
Claim 13
Dependent Claim
19 words
A zirconium alloy having superior corrosion resistance as claimed in claim 5, wherein the annealing temperature is 400°-640? C.
Claim 14
Dependent Claim
49 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1 or claim 7, wherein the total amount of said at least one kind of Fe and Cr; or at least one element of Fe and Cr, and Ni; in said solid-solution is at least 0.28 weight %.
Claim 15
Dependent Claim
23 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1, wherein the alloy after final annealing is substantially all recrystallization structure.
Claim 16
Dependent Claim
33 words
A zirconium alloy having superior corrosion resistance as claimed in claim 1, wherein the solid-solution of the zirconium alloy is provided by performing the solution heat treatment at a temperature of 825°-965° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-11 | 1990-11-10 | 1991-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-11 | 1994-11-10 | 1995-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-11 | 1998-11-10 | 1999-05-12 | $7700.00 | Window Closed / Lapsed |