US4050143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing dense metal tubes or the like
Assignee: Granges Nyby AB
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Filing: 1975-04-18
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Granted: 1977-09-27
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Expires: 1995-04-18
Abstract
Abstract A method and a capsule and a blank for producing tubes, bars or similar profiled elongated dense metal objects, preferably in stainless steel qualities, by single or multi-stage extrusion of capsules which are filled with powder of metals or metal alloys or mixtures thereof or with mixtures of powder of metals and/or metal alloys with ceramic powder and sealed and which are adapted in their form to the desired object or intermediate product, as starting material a powder being used which consists at least predominantly of substantially spherical grains and the capsule filled with said powder and sealed being compressed by means of cold-isostatic pressure acting all round until the density of the powder reaches at least 80% of the theoretical density.
Inventors
- 👤 Christer Aslund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:19
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/02; B22F3/04; B22F3/12; B22F3/1208; B22F3/20; Y; Y10; Y10S; Y10S29/00; Y10S29/031
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
144 words
In a method for producing an elongated dense metal object in which metal powder is sealed in a metal container, the metal container with the metal powder therein is partially compressed in a first compression step and the partially compressed metal container so formed is extruded at elevated temperature in a second compression step, the improvement wherein (1) the metal particles of said metal powder are substantially spherical, (2) said container is formed from a ductile metal, (3) the wall thickness of said container is at most 5% of the outer diameter of said container, (4) said metal contaner is subjected to cold-isostatic pressure acting on all surfaces of said container during said first compression step, and (5) said metal container is compressed until the density of the metal powder therein reaches at least 80% of the theoretical density during said first compression step.
Claim 2
Dependent Claim
144 words
In a method for producing an elongated dense metal object in which metal powder is sealed in a metal container, the metal container with the metal powder therein is partially compressed in a first compression step and the partially compressed metal container so formed is extruded at elevated temperature in a second compression step, the improvement wherein (1) the metal particles of said metal powder are substantially spherical, (2) said container is formed from a ductile metal, (3) the wall thickness of said container is at most 5% of the outer diameter of said container, (4) said metal contaner is subjected to cold-isostatic pressure acting on all surfaces of said container during said first compression step, and (5) said metal container is compressed until the density of the metal powder therein reaches at least 80% of the theoretical density during said first compression step.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein the wall thickness of said container is less than 3% of the outer diameter of said container.
Claim 4
Dependent Claim
20 words
A method according to claim 1, wherein the wall thickness of said container is between about 0.1 to 5 mm.
Claim 5
Dependent Claim
21 words
A method according to claim 1, wherein said metal powder has a grain size or diameter of less than 1 mm.
Claim 6
Dependent Claim
25 words
A method according to claim 1, wherein said container is subjected to an isostatic pressure of at least 1500 bar during said first compression step.
Claim 7
Dependent Claim
18 words
A method according to claim 1, wherein said container is filled with an inert gas prior to sealing.
Claim 8
Dependent Claim
32 words
A method according to claim 1, wherein said first compression step is continued until the density of the metal powder in said container is between 80% and 90% of the theoretical density.
Claim 9
Dependent Claim
24 words
A method according to claim 2, wherein the wall thickness of said container is less than 1% of the outer diameter of said container.
Claim 10
Dependent Claim
19 words
A method according to claim 3, wherein the wall thickness of said container is between 0.2 and 3 mm.
Claim 11
Dependent Claim
19 words
A method according to claim 4, wherein said metal powder has a grain size of less than 0.6 mm.
Claim 12
Dependent Claim
44 words
A method according to claim 1, wherein said container is vibrated as said metal powder is filled therein whereby the density of the metal powder in said metal container is between 60 to 70% of the theoretical density prior to said first compression step.
Claim 13
Dependent Claim
12 words
A method according to claim 11, wherein said container is vibrated ultrasonically.
Claim 14
Dependent Claim
24 words
A method according to claim 5, wherein said container is subjected to isostatic pressure of at least 5000 bar during said first compression step.
Claim 15
Dependent Claim
47 words
A method according to claim 1, wherein said container includes at least one concentric partition dividing the interior of said container into at least two regions, each of said regions being filled with metal powder having a different composition from the metal powder filling the other regions.
Claim 16
Dependent Claim
14 words
A method according to claim 1, wherein said container is evacuated prior to sealing.
Claim 17
Dependent Claim
15 words
A method according to claim 1, wherein said metal powder is formed from stainless steel.
Claim 18
Dependent Claim
22 words
A method according to claim 16, wherein the length to diameter ratio of said elongated dense metal object is greater than 1.
References Cited (Backward Citations)
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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) | 1980-09-26 | 1981-03-28 | 1981-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-26 | 1985-03-28 | 1985-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-26 | 1989-03-28 | 1989-09-27 | $7700.00 | Window Closed / Lapsed |