US4231507A
Expired / Lapsed
US
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High-temperature, high-pressure bonding of nested tubular metallic components
Assignee: United States Department of Energy
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Filing: 1979-01-09
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Granted: 1980-11-04
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Expires: 1999-01-09
Abstract
Abstract This invention is a tool for effecting high-temperature, high-compression bonding between the confronting faces of nested, tubular, metallic components. In a typical application, the tool is used to produce tubular target assemblies for irradiation in nuclear reactors or particle accelerators, the target assembly comprising a uranium foil and an aluminum-alloy substrate. The tool preferably is composed throughout of graphite. It comprises a tubular restraining member in which a mechanically expandable tubular core is mounted to form an annulus with the member. The components to be bonded are mounted in nested relation in the annulus. The expandable core is formed of individually movable, axially elongated segments whose outer faces cooperatively define a cylindrical pressing surface and whose inner faces cooperatively define two opposed, inwardly tapered, axial bores. Tapered rams extend respectively into the bores. The loaded tool is mounted in a conventional hot-press provided with evacuation means, heaters for maintaining its interior at bonding temperature, and hydraulic cylinders for maintaining a selected inwardly directed pressure on the tapered rams. With the hot-press evacuated and the loaded tool at the desired temperature, the cylinders are actuated to apply the selected pressure to the rams. The rams in turn expand the segmented core to maintain the nested components in compression against the restraining member. These conditions are maintained until the confronting faces of the nested components are joined in a continuous, uniform bond characterized by high thermal conductivity.
Inventors
- 👤 Thomas C. Quinby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:01
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
148 words
A graphite tool for use in diffusion-bonding a plurality of nested tubular metallic components to form a unitary tubular assembly thereof, said tool comprising: a tubular restraining member having an axis, a tubular core coaxially mounted within said member and defining therewith an annulus for reception of said nested components, said core being formed of a plurality of axially elongated segments each displaceable outwardly away from said axis, said segments having confronting curved inner faces cooperatively defining opposed, inwardly tapering, axially extending bores which extend respectively from the ends of said core to the transverse midplane thereof, and independently movable, solid, tapered rams respectively extending into said bores and movable inwardly therein to the region of said midplane to be in contact with and exert radially directed force on at least most of the interior surface of said core and compress the received nested components against said member.
Claim 2
Dependent Claim
148 words
A graphite tool for use in diffusion-bonding a plurality of nested tubular metallic components to form a unitary tubular assembly thereof, said tool comprising: a tubular restraining member having an axis, a tubular core coaxially mounted within said member and defining therewith an annulus for reception of said nested components, said core being formed of a plurality of axially elongated segments each displaceable outwardly away from said axis, said segments having confronting curved inner faces cooperatively defining opposed, inwardly tapering, axially extending bores which extend respectively from the ends of said core to the transverse midplane thereof, and independently movable, solid, tapered rams respectively extending into said bores and movable inwardly therein to the region of said midplane to be in contact with and exert radially directed force on at least most of the interior surface of said core and compress the received nested components against said member.
Claim 3
Dependent Claim
162 words
A graphite tool for use in the high-temperature, high-pressure bonding of a plurality of nested tubular metallic components to form a unitary tubular assembly thereof, said tool comprising: a tubular restraining member having an axis; a mechanically expandable tubular core mounted coaxially within said restraining member, said core being formed of a plurality of axially elongated, radially displaceable segments having curved outer faces which cooperatively define a cylindrical pressing surface which with said restraining member defines an annulus for accommodating said nested components, said segments having curved inner faces cooperatively defining two opposed and inwardly tapering axial bores which extend respectively from the ends of said core to the transverse midplane thereof; and solid, independently movable, tapered rams of circular cross section respectively fitted in said bores and movable inwardly therein to positions adjacent said midplane to contact most of the interior surface of said core and urge said segments radially outward to compress uniformly said nested components against said restraining member.
Claim 4
Dependent Claim
162 words
A graphite tool for use in the high-temperature, high-pressure bonding of a plurality of nested tubular metallic components to form a unitary tubular assembly thereof, said tool comprising: a tubular restraining member having an axis; a mechanically expandable tubular core mounted coaxially within said restraining member, said core being formed of a plurality of axially elongated, radially displaceable segments having curved outer faces which cooperatively define a cylindrical pressing surface which with said restraining member defines an annulus for accommodating said nested components, said segments having curved inner faces cooperatively defining two opposed and inwardly tapering axial bores which extend respectively from the ends of said core to the transverse midplane thereof; and solid, independently movable, tapered rams of circular cross section respectively fitted in said bores and movable inwardly therein to positions adjacent said midplane to contact most of the interior surface of said core and urge said segments radially outward to compress uniformly said nested components against said restraining member.
Claim 5
Independent Claim
225 words
The method of bonding a metallic foil to a metallic substrate to form a unitary tubular assembly thereof, said method comprising: providing a bonding tool comprising a graphite tubular restraining member; a mechanically expandable graphite core coaxially mounted in said member, said core being formed of axially elongated and individually radially displaceable segments having curved outer faces which cooperatively define a cylindrical pressing surface which with said member defines an annulus, said segments having curved inner faces which cooperatively define two opposed and inwardly tapering axial bores; and independently movable, solid, tapered graphite rams respectively extending into said bores and movable inwardly therein to positions adjacent said midplane to urge said segments and pressing surface toward said member; positioning said foil and substrate in nested relation in said annulus, each of the members so positioned being in the form of a tube having a pair of abutting edges; maintaining the resulting loaded tool in a non-reactive atmosphere and at an elevated temperature promoting bonding of said foil and substrate; and while the loaded tool is so maintained, maintaining a selected inwardly directed force on each of said rams to exert radially directed force on most of the interior surface of said core and compress said foil and substrate against said restraining member to effect uniform bonding of the confronting faces of said foil and substrate.
Claim 6
Independent Claim
225 words
The method of bonding a metallic foil to a metallic substrate to form a unitary tubular assembly thereof, said method comprising: providing a bonding tool comprising a graphite tubular restraining member; a mechanically expandable graphite core coaxially mounted in said member, said core being formed of axially elongated and individually radially displaceable segments having curved outer faces which cooperatively define a cylindrical pressing surface which with said member defines an annulus, said segments having curved inner faces which cooperatively define two opposed and inwardly tapering axial bores; and independently movable, solid, tapered graphite rams respectively extending into said bores and movable inwardly therein to positions adjacent said midplane to urge said segments and pressing surface toward said member; positioning said foil and substrate in nested relation in said annulus, each of the members so positioned being in the form of a tube having a pair of abutting edges; maintaining the resulting loaded tool in a non-reactive atmosphere and at an elevated temperature promoting bonding of said foil and substrate; and while the loaded tool is so maintained, maintaining a selected inwardly directed force on each of said rams to exert radially directed force on most of the interior surface of said core and compress said foil and substrate against said restraining member to effect uniform bonding of the confronting faces of said foil and substrate.
Claim 7
Dependent Claim
16 words
The method of claim 3 wherein said foil is uranium and said substrate is aluminum alloy.
References Cited (Backward Citations)
US2226078A
Cited
US2424878A
Cited
US2850798A
Cited
FR1379684A
Cited
US3559274A
Cited
US3372464A
Cited
US3481024A
Cited
US3550254A
Cited
US3703032A
Cited
US3762032A
Cited
US3955093A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-04 | 1984-05-05 | 1984-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-04 | 1988-05-05 | 1988-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-04 | 1992-05-05 | 1992-11-04 | $7700.00 | Window Closed / Lapsed |