US4065328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High strength Sn-Mo-Nb-Zr alloy tubes and method of making same
Assignee: Atomic Energy of Canada Ltd AECL
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Filing: 1976-04-28
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Granted: 1977-12-27
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Expires: 1996-04-28
Abstract
Abstract Tubes for use in nuclear reactors fabricated from a quaternary alloy comprising 2.5-4.0 wt% Sn, 0.5-1.5 wt% Mo, 0.5-1.5 wt% Nb, balance essentially Zr. The tubes are fabricated by a process of hot extrusion, heat treatment, cold working to size and age hardening, so as to produce a microstructure comprising elongated α grains with an acicular transformed β grain boundary phase.
Inventors
- 👤 Brian A. Cheadle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:52
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/186; C22C; C22C16/00; Y; Y10; Y10S; Y10S376/00; Y10S376/90
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
110 words
In a method of fabricating extruded alloy tubes from an alloy consisting essentially of Sn 2.5-4.0%, Mo 0.5-1.5%, Nb 0.5-1.5%, O 800-1300 ppm, balance Zr and incidental impurities, in which said alloy is preheated to a temperature in the range 850°-900° C, extruded through a tube forming die, cold worked to size and age hardened by heating at a temperature in the range between 400° and 500° C, the improvement comprising rapidly cooling said extruded tube immediately following extrusion at a rate of at least 30° C per second so as to develop a microstructure comprising hexagonal α grains elongated in the extrusion direction and an acicular grain boundary phase.
Claim 2
Dependent Claim
110 words
In a method of fabricating extruded alloy tubes from an alloy consisting essentially of Sn 2.5-4.0%, Mo 0.5-1.5%, Nb 0.5-1.5%, O 800-1300 ppm, balance Zr and incidental impurities, in which said alloy is preheated to a temperature in the range 850°-900° C, extruded through a tube forming die, cold worked to size and age hardened by heating at a temperature in the range between 400° and 500° C, the improvement comprising rapidly cooling said extruded tube immediately following extrusion at a rate of at least 30° C per second so as to develop a microstructure comprising hexagonal α grains elongated in the extrusion direction and an acicular grain boundary phase.
Claim 3
Dependent Claim
32 words
In a method of fabricating extruded alloy tubes as claimed in claim 1, the improvement wherein said tube is cooled after extrusion at a rate of 30° to 100° C per second.
Claim 4
Dependent Claim
28 words
In a method of fabricating alloy tubes as claimed in claim 1 the improvement comprising extruding said tubes at an extrusion ratio in the range 5:1 to 25:1.
Claim 5
Dependent Claim
22 words
A method of fabricating alloy tubes as claimed in claim 3 wherein said tubes are extruded at an extrusion ratio of 15:1.
Claim 6
Dependent Claim
22 words
A method of fabricating alloy tubes as claimed in claim 2 wherein said tubes are cooled after extrusion in an air blast.
Claim 7
Dependent Claim
22 words
A method of fabricating alloy tubes as claimed in claim 2 wherein said tubes are cooled after extrusion by water spray cooling.
Claim 8
Dependent Claim
13 words
A high strength extruded alloy tube made by the process of claim 1.
Claim 9
Dependent Claim
19 words
An extruded alloy tube as claimed in claim 7 having an ultimate tensile strength in the range 550-725 MPa.
Claim 10
Dependent Claim
24 words
An extruded alloy tube as claimed in claim 7 comprising 3.3% Sn, 1.0% Mo, 0.75% Nb, O 800-1300 ppm, balance Zr and incidental impurities.
References Cited (Backward Citations)
GB932336A
Cited
US4000013A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |