US3889349A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brazing metal alloys
Assignee: Ford Motor Co
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Filing: 1973-06-08
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Granted: 1975-06-17
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Expires: 1993-06-08
Abstract
Abstract A method of joining compacted powdered parts is disclosed using a relatively low temperature melting infiltrant (such as copper) to reduce internal porosity of the powder parts at least at the bonding margins thereof and in a predetermined unsaturated amount. A higher melting brazing composition (such as high carbon-iron) is used to bond the parts. The weak capillary attraction with high carbon-iron causes preferential infiltration of the powdered parts to a limited degree.
Inventors
- 👤 Sydney M Kaufman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:01
CPC Classifications
B; B22; B22F; B22F7/00; B22F7/02; B22F3/00; B22F3/24; B22F3/26
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
147 words
A METHOD OF BRAZING POROUS FERRUGINOUS MATERIAL, COMPRISING: A. COMPACTING IRON BASE POWDER TO FORM A PAIR OF MATING ARTICLE PORTIONS, B. ARRANRING AN IRON BASE POWDER INFILTRANT HAVING A MELTING TEMPERATURE SUBSTANTIALLY LOWER THAN HIGH CARBON-IRON MATERIALS, SAID ARRANGEMENT PLACING SAID INFILTRANT ADJACENT A SURFACE OF SAID ARTICLE PORTIONS, C. ARRANGING A BRAZING MATERIAL FOR INTERCONNECTING SAID MATING PORTIONS, SAID BRAZING MATERIAL HAVING A WEAKER CAPILLARY ATTRACTION WITH SAID INFILTRANT THAN WITH SAID IRON BASE POWDER, D. SUBJECTING SAID CONTIGOUSLY ARRANGED ARTICLE PORTIONS, BRAZING MATERIAL AND INFILTRANT TO A STEPPED SINTERING OPERATION WHEREBY SAID INFILTRANT IS FIRST PERMITTED TO MELT AND MIGRATE INTO SAID ARTICLE PORTIONS IN A CONTROLLED MANNER SHORT OF SAID BRAZING MATERIAL, SAID BRAZING MATERIAL THEN MELTING TO INFILTRATE SAID ARTICLE PORTIONS ONLY CLOSELY ADJACENT TO SAID MATING SURFACES THEREBY PROVIDING A DURABLE BOND BETWEEN SAID ARTICLE PORTIONS ON COOLING TO AMBIENT CONDITIONS.
Claim 2
Independent Claim
147 words
A METHOD OF BRAZING POROUS FERRUGINOUS MATERIAL, COMPRISING: A. COMPACTING IRON BASE POWDER TO FORM A PAIR OF MATING ARTICLE PORTIONS, B. ARRANRING AN IRON BASE POWDER INFILTRANT HAVING A MELTING TEMPERATURE SUBSTANTIALLY LOWER THAN HIGH CARBON-IRON MATERIALS, SAID ARRANGEMENT PLACING SAID INFILTRANT ADJACENT A SURFACE OF SAID ARTICLE PORTIONS, C. ARRANGING A BRAZING MATERIAL FOR INTERCONNECTING SAID MATING PORTIONS, SAID BRAZING MATERIAL HAVING A WEAKER CAPILLARY ATTRACTION WITH SAID INFILTRANT THAN WITH SAID IRON BASE POWDER, D. SUBJECTING SAID CONTIGOUSLY ARRANGED ARTICLE PORTIONS, BRAZING MATERIAL AND INFILTRANT TO A STEPPED SINTERING OPERATION WHEREBY SAID INFILTRANT IS FIRST PERMITTED TO MELT AND MIGRATE INTO SAID ARTICLE PORTIONS IN A CONTROLLED MANNER SHORT OF SAID BRAZING MATERIAL, SAID BRAZING MATERIAL THEN MELTING TO INFILTRATE SAID ARTICLE PORTIONS ONLY CLOSELY ADJACENT TO SAID MATING SURFACES THEREBY PROVIDING A DURABLE BOND BETWEEN SAID ARTICLE PORTIONS ON COOLING TO AMBIENT CONDITIONS.
Claim 3
Dependent Claim
20 words
The method as in claim 1, in which said iron base powder has a carbon content no greater than 1.5%.
Claim 4
Dependent Claim
23 words
The method as in claim 1, in which said brazing material is an iron based composition having a carbon content greater than 2.03%.
Claim 5
Dependent Claim
12 words
The method as in claim 1, in which said infiltrant contains copper.
Claim 6
Dependent Claim
44 words
The method as in claim 1, in which said brazing material is an iron base material having a carbon content effective to cause a eutectic reaction at temperature levels below the melting temperature of the iron base powder and above that of the infiltrant.
Claim 7
Dependent Claim
29 words
The method as in claim 1, in which said brazing material consists of iron and about 5% graphite, the stepped sintering operation being carried out in a reducing atmosphere.
Claim 8
Dependent Claim
33 words
The method as in claim 6, in which the atmosphere is non-oxidizing and may consist of either pure hydrogen or generator gas comprised of about 40% nitrogen, 40% hydrogen and 20% carbon monoxide.
Claim 9
Dependent Claim
25 words
The method as in claim 5, in which said brazing material is an alloy consisting of about 8.5% manganese, 4.0% carbon and the balance iron.
Claim 10
Dependent Claim
23 words
The method as in claim 1, in which said infiltrant is melted to occupy between 9-95% of the porosity of the particle portions.
Claim 11
Dependent Claim
24 words
The method as in claim 1, in which the infiltrant is formed as powder compact arranged along the outer sides of the mated portions.
Claim 12
Dependent Claim
25 words
The method as in claim 1, in which the infiltrant is added as a constituent powder to the powder mixture for making the particle portions.
Claim 13
Dependent Claim
26 words
The method as in claim 1, in which the brazing material is prepared as a solid slab for arrangement between the particle portions during stepped sintering.
Claim 14
Dependent Claim
28 words
The method as in claim 1, in which the brazing material is prepared as a powder additive only to the outermost margins of the particle portions during cOmpaction.
Claim 15
Dependent Claim
30 words
The method as in claim 1, in which the brazing material is a powder admixed with about 5% graphite and independently compacted onto the mating surfaces of said particle portions.
References Cited (Backward Citations)
US3138862A
Cited
US3147089A
Cited
US3326678A
Cited
US3307924A
Cited
US3652261A
Cited
US3795511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |