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US5114470A
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Producing void-free metal alloy powders by melting as well as atomization under nitrogen ambient
Assignee: United States Department of Commerce
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Filing: 1990-10-04
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Granted: 1992-05-19
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Expires: 2010-10-04
Abstract
Abstract A method of producing nitrogenated metal alloys which involves melting a al alloy under a nitrogen atmosphere and subsequently gas atomizing the molten alloy with nitrogen gas has been found to produce alloys powders having a high nitrogen content and a minimum amount of hollow particles. The resulting alloy powders which demonstrate superior mechanical properties and heat and chemical resistance are easily fabricated into articles utilizing powder metallurgical processes.
Inventors
- 👤 Francis S. Biancaniello
- 👤 Gregg N. Janowski
- 👤 Stephen D. Ridder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:33
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/04; B; B22; B22F; B22F3/00; B22F3/22; B22F3/225; C22C1/00; C22C1/10; C22C1/1036; C22C1/1042; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0285; B22F2998/00; B22F2999/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
93 words
A method of producing a nitrogenated metal alloy powder which comprises the following steps: (a) melting a metal alloy under a nitrogen atmosphere to increase the nitrogen content of said alloy and thereafter (b) subjecting said molten alloy to a gas atomizing process to produce solid, substantially spherical shaped nitrogenated metal alloy particles, wherein nitrogen is utilized as the atomizing gas in said gas atomizing process and said gas atomization process is controlled so that nitrogen provided to increase said nitrogen content in step (a) is absorbed into the resulting metal alloy particles.
Claim 2
Independent Claim
93 words
A method of producing a nitrogenated metal alloy powder which comprises the following steps: (a) melting a metal alloy under a nitrogen atmosphere to increase the nitrogen content of said alloy and thereafter (b) subjecting said molten alloy to a gas atomizing process to produce solid, substantially spherical shaped nitrogenated metal alloy particles, wherein nitrogen is utilized as the atomizing gas in said gas atomizing process and said gas atomization process is controlled so that nitrogen provided to increase said nitrogen content in step (a) is absorbed into the resulting metal alloy particles.
Claim 3
Dependent Claim
30 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein said nitrogen containing atmosphere utilizing during the melting is at a pressure of about 1 atmosphere.
Claim 4
Dependent Claim
34 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein less than about 1 percent of the metal alloy powder particles produced by the gas atomization step include hollow particles.
Claim 5
Dependent Claim
32 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein said metal alloy is selected from the group consisting of steels, nickel alloys, aluminum alloys and titanium alloys.
Claim 6
Dependent Claim
33 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein said metal alloy includes one or more elements which are capable of reacting with nitrogen to form a nitride.
Claim 7
Dependent Claim
30 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein the average particle size of the resulting metal alloy powder is less than about 100 μm.
Claim 8
Dependent Claim
31 words
A method of producing a nitrogenated metal alloy powder according to claim 1, wherein more that about 30-50 percent of said nitrogenated metal alloy particles rae greater than about 10 μm.
Claim 9
Dependent Claim
20 words
A method of producing a nitrogenated metal alloy powder according to claim 4, wherein said metal alloy is stainless steel.
Claim 10
Dependent Claim
22 words
A method of producing a nitrogenated metal alloy powder according to claim 4 wherein said metal alloy is a nickel-based super alloy.
Claim 11
Dependent Claim
21 words
A method of producing a nitrogenated metal alloy powder according to claim 8, wherein said metal alloy is austenitic stainless steel.
Claim 12
Dependent Claim
65 words
A method of producing a nitrogenated metal alloy powder according to claim 10, wherein said austenitic stainless steel comprises 0.3 wt. % C; 2.0 wt. % Mn; 1.0 wt. % Si; 18.0 to 22.0 wt. % Cr; 8.0 to 12.0 wt. % Ni and a balance of Fe prior to melting and includes up to about 0.21 wt. % nitrogen after the gas atomization step.
Claim 13
Independent Claim
97 words
A method of fabricating a metal alloy article which comprises consolidating a nitrogenated metal alloy powder produced by: (a) melting a metal alloy under a nitrogen atmosphere to increase the nitrogen content of said alloy; and thereafter (b) subjecting said molten alloy to a gas atomization process to produce solid, substantially spherical shaped nitrogenated metal alloy particles, wherein nitrogen is utilized as the atomizing gas in said gas atomizing process and said gas atomization process is controlled so that nitrogen provided to increase said nitrogen content in step (a) is absorbed into the resulting metal alloy particles.
Claim 14
Independent Claim
97 words
A method of fabricating a metal alloy article which comprises consolidating a nitrogenated metal alloy powder produced by: (a) melting a metal alloy under a nitrogen atmosphere to increase the nitrogen content of said alloy; and thereafter (b) subjecting said molten alloy to a gas atomization process to produce solid, substantially spherical shaped nitrogenated metal alloy particles, wherein nitrogen is utilized as the atomizing gas in said gas atomizing process and said gas atomization process is controlled so that nitrogen provided to increase said nitrogen content in step (a) is absorbed into the resulting metal alloy particles.
Claim 15
Dependent Claim
29 words
A method of fabricating a metal alloy article according to claim 12, wherein said nitrogenated metal alloy powder is consolidated by a hot isostatic pressing or injection molding process.
Claim 16
Dependent Claim
33 words
A method of fabricating a metal alloy article according to claim 12, wherein less than about 1 percent of the metal alloy powder particles produced by the gas atomization step include hollow particles.
Claim 17
Dependent Claim
31 words
A method of fabricating a metal alloy article according to claim 12 wherein said metal alloy is selected from the group consisting of steels, nickel alloys, aluminum alloys and titanium alloys.
Claim 18
Dependent Claim
32 words
A method of fabricating a metal alloy article according to claim 12, wherein said metal alloy includes one or more elements which are capable of reacting with nitrogen to form a nitride.
Claim 19
Dependent Claim
29 words
A method of fabricating a metal alloy article according to claim 12, wherein the average particle size of the resulting metal alloy powder is less than about 100 μm.
Claim 20
Dependent Claim
30 words
A method of fabricating a metal alloy article according to claim 12, wherein more that about 30-50 percent of said nitrogenated metal alloy particles are greater than about 10 μm.
Claim 21
Dependent Claim
19 words
A method of fabricating a metal alloy article according to claim 15, wherein said metal alloy is stainless steel.
Claim 22
Dependent Claim
21 words
A method of fabricating a metal alloy article according to claim 15 wherein said metal alloy is a nickel-based super alloy.
Claim 23
Dependent Claim
20 words
A method of fabricating a metal alloy article according to claim 19, wherein said metal alloy is austenitic stainless steel.
Claim 24
Dependent Claim
64 words
A method of fabricating a metal alloy article according to claim 21 wherein said austenitic stainless steel comprises 0.3 wt. % C; 2.0 wt. % Mn; 1.0 wt. % Si; 18.0 to 22.0 wt. % Cr; 8.0 to 12.0 wt. % Ni and a balance of Fe prior to melting and includes up to about 0.21 wt. % nitrogen after the gas atomization step.
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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) | 1995-05-19 | 1995-11-18 | 1996-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-19 | 1999-11-18 | 2000-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-19 | 2003-11-18 | 2004-05-19 | $7700.00 | Window Closed / Lapsed |