Patent US4878840A successfully refreshed from Google Patents.
Patent US3987658A successfully refreshed from Google Patents.
US3987658A
Expired / Lapsed
US
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Graphite forging die
Assignee: RTX Corp
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Filing: 1975-12-12
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Granted: 1976-10-26
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Expires: 1995-12-12
Abstract
Abstract Graphite having a compressive strength at room temperature of at least 10,000 psi is an improved die material useful in the forging of high strength alloys which are in a temporary condition of low strength and high ductility in hot die means.
Inventors
- 👤 Robert Andrew Herold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:11
CPC Classifications
B; B21; B21K; B21K3/00; B21K3/04; B21J; B21J13/00; B21J13/02; B21J5/00; B21J5/02; Y; Y10; Y10S; Y10S72/00; Y10S72/70
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
49 words
In an apparatus for forging a high strength alloy, which is in a temporary condition of low strength and high ductility, in hot die means at an elevated temperature, the improvement which comprises: die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 2
Dependent Claim
49 words
In an apparatus for forging a high strength alloy, which is in a temporary condition of low strength and high ductility, in hot die means at an elevated temperature, the improvement which comprises: die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 3
Dependent Claim
24 words
The apparatus of claim 1 in which the die means comprises graphite having a compressive strength of at least 15,000 psi at room temperature.
Claim 4
Dependent Claim
13 words
The apparatus of claim 1 in which the graphite is in molded form.
Claim 5
Dependent Claim
15 words
The apparatus of claim 1 in which the graphite is in woven and sintered form.
Claim 6
Dependent Claim
67 words
In a forging process wherein a high strength alloy in a temporary condition of low strength and high ductility is deformed in hot die means at a temperature which will maintain the alloy in said condition until the desired shape is produced, the improvement which comprises: deforming said alloy in hot die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 7
Dependent Claim
67 words
In a forging process wherein a high strength alloy in a temporary condition of low strength and high ductility is deformed in hot die means at a temperature which will maintain the alloy in said condition until the desired shape is produced, the improvement which comprises: deforming said alloy in hot die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 8
Dependent Claim
23 words
The method of claim 5 wherein said die means comprise graphite having a compressive strength of at least 15,000 psi at room temperature.
Claim 9
Dependent Claim
12 words
The method of claim 5 wherein the graphite is in molded form.
Claim 10
Dependent Claim
14 words
The method of claim 5 wherein the graphite is in woven and sintered form.
Claim 11
Dependent Claim
19 words
The method of claim 5 wherein a nonoxidizing atmosphere is maintained around the die means during heating and forging.
Claim 12
Dependent Claim
19 words
The method of claim 5 wherein the alloy is deformed at a strain rate of 0.1 in/in/min or less.
Claim 13
Dependent Claim
15 words
The method of claim 5 wherein said alloy is adapted to gas turbine engine use.
Claim 14
Dependent Claim
12 words
The method of claim 11 wherein said alloy is a nickel-base superalloy.
Claim 15
Dependent Claim
90 words
In a method of fabricating an article from a high strength alloy billet wherein the billet is worked compressively to place the alloy in a temporary condition of low strength and high ductility, forged in hot die means at a temperature which will maintain the alloy in said condition and heat treated to restore the alloy to its normal condition of high strength and hardness, the improvement which comprises: forging the billet in hot die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 16
Dependent Claim
90 words
In a method of fabricating an article from a high strength alloy billet wherein the billet is worked compressively to place the alloy in a temporary condition of low strength and high ductility, forged in hot die means at a temperature which will maintain the alloy in said condition and heat treated to restore the alloy to its normal condition of high strength and hardness, the improvement which comprises: forging the billet in hot die means comprising graphite having a compressive strength at room temperature of at least 10,000 psi.
Claim 17
Dependent Claim
23 words
The method of claim 13 wherein said die means comprise graphite having a compressive strength of at least 15,000 psi at room temperature.
Claim 18
Dependent Claim
14 words
The method of claim 13 wherein the article is a gas turbine engine part.
Claim 19
Dependent Claim
15 words
The method of claim 13 wherein the alloy is adapted to gas turbine engine use.
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) | 1979-10-26 | 1980-04-26 | 1980-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-26 | 1984-04-26 | 1984-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-26 | 1988-04-26 | 1988-10-26 | $7700.00 | Window Closed / Lapsed |