US4934580A
Expired / Lapsed
US
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Method of making superplastically formed and diffusion bonded articles and the articles so made
Assignee: Barnes Group Inc
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Filing: 1988-12-27
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Granted: 1990-06-19
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Expires: 2008-12-27
Abstract
Abstract Methods of making superplastically formed and diffusion bonded articles are disclosed as well as the articles made from such methods. Metal sheets are superplastically formed and diffusion bonded in a manner such that pillows are formed on respective outer surfaces thereof, providing a cellular structure interconnected by channels permitting control of gas pressure with the cells. The cellular structure can, in one embodiment, be twisted and the cells can be inflated through superplastic forming. The twisted cellular structure is particularly useful as an intermediate stiffener for an airfoil.
Inventors
- 👤 Marvin M. Sutton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:42
CPC Classifications
B; B23; B23K; B23K20/00; B21; B21D; B21D13/00; B21D26/00; B21D26/02; B21D26/053; B21D26/055; B21D26/059; B21D47/00; Y; Y10; Y10S; Y10S72/00; Y10S72/709; Y10T; Y10T428/00; Y10T428/12; Y10T428/1234; Y10T428/12389; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
119 words
A method of fabricating a cellular structure, comprising: (a) providing at least one metal sheet capable of undergoing superplastic forming; (b) applying pressure to upset said sheet along a ribbon surface defining in its interstices an array of polygonal voids interconnected with one another by reliefs in the ribbon surface, said pressure being sufficient to reduce the thickness of the sheet along the ribbon surface by between a few and about 10%, said pressure being applied at a sufficient temperature and for a sufficient time for the metal to flow into the areas of the polygonal voids and form pillows therein interconnected by channels corresponding to said reliefs, said pillows and channels being raised relative to the ribbon surface.
Claim 2
Independent Claim
119 words
A method of fabricating a cellular structure, comprising: (a) providing at least one metal sheet capable of undergoing superplastic forming; (b) applying pressure to upset said sheet along a ribbon surface defining in its interstices an array of polygonal voids interconnected with one another by reliefs in the ribbon surface, said pressure being sufficient to reduce the thickness of the sheet along the ribbon surface by between a few and about 10%, said pressure being applied at a sufficient temperature and for a sufficient time for the metal to flow into the areas of the polygonal voids and form pillows therein interconnected by channels corresponding to said reliefs, said pillows and channels being raised relative to the ribbon surface.
Claim 3
Dependent Claim
19 words
A method as set forth in claim 1 wherein said temperature is sufficient to render the metal sheets superplastic.
Claim 4
Dependent Claim
58 words
A method as set forth in claim 2 wherein two metal sheets are provided in face-to-face relation and the pressure to upset them is provided by at least one platen forming said ribbon surface, and an opposing surface, said platen and opposing surface being brought together against positive stops to a separation corresponding to said reduction in thickness.
Claim 5
Dependent Claim
16 words
A method as set forth in claim 3 wherein said opposing surface is a planar surface.
Claim 6
Dependent Claim
74 words
A method as set forth in claim 3 wherein the opposing surface is a second platen forming a second ribbon surface corresponding to the first ribbon surface of the first recited platen, said platens having corresponding reliefs, such that the two metal sheets subject to such upset pressure between them form pillows raised in opposite directions forming a network of cells interconnected by channels accessible through a port at the periphery of said sheets.
Claim 7
Dependent Claim
48 words
A method as set forth in claim 5 wherein such ribbon surface is of substantially constant width between about 1/32 and 1/8 inch, all edges of the platens forming the ribbon surface being rounded sufficiently to avoid sharp corners capable of causing undue stress in the metal sheets.
Claim 8
Dependent Claim
27 words
A method as set forth in claim 6 wherein the shape of said polygonal voids is selected from the group consisting of hexagons, octagons, decagons and dodecagons.
Claim 9
Dependent Claim
27 words
A method as set forth in claim 3 including maintaining the metal sheets ar said temperature sufficiently long to diffusion bond them together along their ribbon surfaces.
Claim 10
Dependent Claim
53 words
A method as set forth in claim 8 where prior to the formed sheets being maintained at said temperature long enough to diffusion bond, they are bonded together about their periphery and provided with means for communicating a source of gas pressure to communicate with the network of cells formed by the sheets.
Claim 11
Dependent Claim
79 words
A method as set forth in claim 1 including diffusion bonding a pair of said metal sheets along their ribbon surfaces and along their periphery to form a preform such that the pillow of the respective sheets form a network of cells interconnected by said channels; providing communicating means for controlling the gas pressure within the network of cells; and applying gas pressure to the cells through the communicating means at superplastic forming temperature to expand them in volume.
Claim 12
Dependent Claim
21 words
A method as set forth in claim 10 wherein the cells are expanded under pressure against a surface limiting their expansion.
Claim 13
Dependent Claim
49 words
A method as set forth in claim 10 wherein the cells are expanded such that substantially all cells on at least one side of the plane of the ribbon are diffusion bonded to adjacent cells to form a cellular reinforcing structure substantially free of voids between adjacent cell walls.
Claim 14
Dependent Claim
29 words
A method as set forth in claim 12 including diffusion bonding said hollow core reinforcing structure to one or more additional metal members to form a stiffened, reinforced structure.
Claim 15
Dependent Claim
49 words
A method as set forth in claim 13 wherein said one or more additional metal members are diffusion bonded to the ends of the cells such that substantially the entire wall surface of the cells is diffusion bonded without voids to adjacent cell walls or to said metal members.
Claim 16
Dependent Claim
29 words
A method as set forth in claim 14 wherein the one or more metal members substantially enclose the entire cellular reinforcing structure to form a hollow core reinforced structure.
Claim 17
Dependent Claim
26 words
A method as set forth in claim 15 where the additional metal members comprise airfoil skins and the resulting structure is a hollow core reinforced airfoil.
Claim 18
Dependent Claim
32 words
A method as set forth in claim 10 including the step of placing the preform, at superplastic temperature, between forming dies shaped to produce a curvature in the plane of the preform.
Claim 19
Dependent Claim
47 words
A method as set forth in claim 17 including introducing positive gas pressure into the network of cells prior to deformation of the preform by the forming dies, and increasing the gas pressure after such curvature has been produced to superplastically expanded the volume of the cells.
Claim 20
Dependent Claim
22 words
A method as set forth in claim 18 wherein said forming dies are shaped to produce a compound curvature in the preform.
Claim 21
Dependent Claim
94 words
A method as set forth in claim 16 including the step of placing the preform, at superplastic forming temperature, between a pair of airfoil skins having a pocket between them with compound curvature; introducing a positive pressure within the cells of the preform; placing the preform in the pocket within the airfoil skins and bringing the skins together to mold the preform to a compound curvature corresponding to that of the pocket; and inflating the preform to conform and diffusion bond its exterior surface to the interior walls of the skins of said pocket.
Claim 22
Dependent Claim
28 words
A method as set forth in claim 15 including inspecting the preform for bond and structural integrity before it is bonded to the one or more metal numbers.
References Cited (Backward Citations)
US3164894A
Cited
US3340589A
Cited
US3632410A
Cited
US3817844A
Cited
US3633267A
Cited
US3800406A
Cited
US3768985A
Cited
US3703032A
Cited
US3809309A
Cited
US3981429A
Cited
US3747197A
Cited
US4029479A
Cited
US3957194A
Cited
US3942231A
Cited
US3920175A
Cited
US4059217A
Cited
US4025036A
Cited
US4087037A
Cited
US4029254A
Cited
US4230614A
Cited
US4312906A
Cited
US4304821A
Cited
US4217397A
Cited
US4197977A
Cited
US4210269A
Cited
US4197978A
Cited
US4204628A
Cited
US4351470A
Cited
US4263375A
Cited
US4218007A
Cited
US4257156A
Cited
US4242176A
Cited
US4292375A
Cited
US4288021A
Cited
US4522859A
Cited
US4526312A
Cited
US4304350A
Cited
US4252263A
Cited
US4350528A
Cited
US4318965A
Cited
US4392602A
Cited
US4394871A
Cited
US4460657A
Cited
US4395310A
Cited
US4549685A
Cited
US4483478A
Cited
US4429824A
Cited
US4444352A
Cited
US4393987A
Cited
US4469757A
Cited
US4415375A
Cited
US4474044A
Cited
US4500033A
Cited
US4534503A
Cited
US4427716A
Cited
US4530197A
Cited
US4509671A
Cited
US4577798A
Cited
US4603808A
Cited
US4658362A
Cited
US4641334A
Cited
US4715055A
Cited
US4642863A
Cited
US4584860A
Cited
US4649249A
Cited
US4708008A
Cited
US4722754A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |