US4834938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making composite articles that include complex internal geometry
Assignee: Dow Chemical Co
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Filing: 1988-04-25
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Granted: 1989-05-30
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Expires: 2008-04-25
Abstract
Abstract A process is described for making a composite article without shrinkage, particularly of ceramic and metal wherein the article includes complex internal surfaces or cavities. The process requires forming an insert body that includes an external surface that corresponds to an internal cavity of the article. The insert body consists of a material having a melting temperature less than that of the article. The process further requires forming a porous compact about the insert body wherein the compact is formed into the substantially the net shape of the article. The compact is made of a material that is wetted by liquid insert material and has a sintering temperature greater than the wetting temperature of the insert material. The process further requires heating the article to a temperature such that the inserts substantially melts and infiltrates the porous compact forming the finished composite article. The process produces products including complex internal surfaces without the necessity of costly and sometimes technically difficult internal machining operations.
Inventors
- 👤 Aleksander J. Pyzik
- 👤 Jack J. Ott
- 👤 Scott J. Jankowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:38
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/45; C04B41/50; C04B41/51; C04B37/00; C04B37/04; C04B37/042; B; B22; B22F; B22F5/00; B22F5/10; C04B35/00; C04B35/515; C04B35/56; C04B35/563; C04B35/622; C04B35/653; C04B41/009; C04B41/4505; C04B41/4523; C04B41/515; C04B41/5155; C04B41/80; C04B41/81; C04B41/85; C04B41/88; B22F2005/103; C04B2235/00; C04B2235/65; C04B2235/656; C04B2235/6565; C04B2237/00; C04B2237/30; C04B2237/32; C04B2237/36; C04B2237/368; Y; Y10; Y10S; Y10S264/00; Y10S264/36
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
130 words
A process for making a composite article having an internal surface or cavity, comprising: (a) forming an insert body, said body having an external surface that corresponds to said internal surface of said article, said insert body consisting of a material that has a wetting temperature less than that of said article; (b) forming a porous compact about said insert body, said compact formed into substantially the net shape of said article, said compact made of a material wetted by said insert material and having a sintering temperature greater than the wetting temperature of said insert material; and (c) heating said article to said wetting temperature such that said insert material substantially melts and infiltrates said porous compact, forming said opposite article having substantially the net shape of said compact.
Claim 2
Dependent Claim
130 words
A process for making a composite article having an internal surface or cavity, comprising: (a) forming an insert body, said body having an external surface that corresponds to said internal surface of said article, said insert body consisting of a material that has a wetting temperature less than that of said article; (b) forming a porous compact about said insert body, said compact formed into substantially the net shape of said article, said compact made of a material wetted by said insert material and having a sintering temperature greater than the wetting temperature of said insert material; and (c) heating said article to said wetting temperature such that said insert material substantially melts and infiltrates said porous compact, forming said opposite article having substantially the net shape of said compact.
Claim 3
Dependent Claim
25 words
The process of claim 1 wherein said insert body material is a metal or glass and said porous compact material is a ceramic or metal.
Claim 4
Dependent Claim
44 words
The process of claim 2 wherein said compact-insert materials are ceramic-metal materials selected from the group consisting of B 4 C-A1, B 4 C-Si, TiB 2 -A1, TiB 2 -Ni, B 4 C-Mg, AlB 12 -A1, SiB 6 -A1, SiB 4 -A1 and SiC-Si.
Claim 5
Dependent Claim
60 words
The process of claim 2 wherein said compact-insert ceramic-glass materials are A1 2 0 3 -(Si0 2 -B 2 0 3 glass), Si 3 N 4 -(Si0 2 -Mg0 glass), Si 3 N 4 -(Si0 2 -Y 2 0 3 glass), Si 3 N 4 -(Mg0-Y 2 0 3 -Ca0-Si0 2 glass), or Si 3 N 4 -(A1 2 glass).
Claim 6
Dependent Claim
14 words
The process of claim 2 wherein said compact-insert metal-metal materials are Ti-Mg or W-Cu.
Claim 7
Dependent Claim
30 words
The process of claim 1 wherein said insert body material is a metal and said compact material is a ceramic and said metal and ceramic are reactive at elevated temperature.
Claim 8
Dependent Claim
19 words
The process of claim 6 wherein said ceramic metal materials are B 4 C-A1 or B 4 C-A1 alloys.
Claim 9
Dependent Claim
33 words
The process of claim 6 or 7 wherein, after said insert material infiltrates said compact, the temperature of said article is adjusted such that said metal and ceramic react to form metal-ceramic phases.
Claim 10
Dependent Claim
20 words
The process of claim 1 wherein, upon heating, said insert material infiltrates and fills all pores of said porous compact.
Claim 11
Dependent Claim
23 words
The process of claim 1 wherein, upon heating, said insert material infiltrates and fills a portion of the pores of said porous compact.
Claim 12
Dependent Claim
39 words
The process of claim 10 wherein, upon heating, said insert material is limited in amount such that it fills all pores of said compact but only adjacent said internal surface of said compact before said insert material is depleted.
Claim 13
Dependent Claim
25 words
The process of claim 1 wherein said heating step proceeds incrementally to said wetting tempeature and is held at said temperature until infiltration is complete.
Claim 14
Dependent Claim
49 words
The process of claim 12 wherein said ceramic-metal materials are B 4 C-A1 or B 4 C-A1 alloys and said heating proceeds at about 10° C./min from about 1000° to 1100° C. and at about 5° C./min from 1100° C. to the maximum desired temperature of about 1200° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-29 | 1992-11-28 | 1993-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-29 | 1996-11-28 | 1997-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-29 | 2000-11-28 | 2001-05-30 | $7700.00 | Window Closed / Lapsed |