US4195764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brazing of powdered metal parts
Assignee: Caterpillar Inc
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Filing: 1977-11-02
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Granted: 1980-04-01
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Expires: 1997-11-02
Abstract
Abstract Disclosed is a method of joining, by brazing, two metal pieces at least one of which is a powdered metal piece, each piece having a joint surface. The method includes the step of plating the joint surface of the powdered metal piece with a thin layer of metal having a relatively high melting point, assembling the pieces with their joint surfaces in substantial abutment, and applying a metal brazing composition having a flow temperature at least about 300°-400° F. or more less than melting point of the plating metal to the joint surfaces while heating the joint with a torch. The method eliminates the need for rigorous temperature control customarily employed in powdered metal brazing.
Inventors
- 👤 Eldred Bogart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:29
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/19; B22; B22F; B22F7/00; B22F7/06; B23K35/00; B23K35/001
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
90 words
A method of brazing two metal pieces, at least one of which is a ferrous powdered metal piece, each having a joint surface, comprising the steps of: plating the joint surface of the ferrous powdered metal piece(s) with a thin layer of nickel; abutting the joint surfaces; applying a silver brazing alloy having a silver content in the range of about 25-70% silver to the surfaces and heating the surfaces with a torch until the brazing alloy flows; and thereafter discontinuing the heating of the surfaces before the nickel flows.
Claim 2
Independent Claim
90 words
A method of brazing two metal pieces, at least one of which is a ferrous powdered metal piece, each having a joint surface, comprising the steps of: plating the joint surface of the ferrous powdered metal piece(s) with a thin layer of nickel; abutting the joint surfaces; applying a silver brazing alloy having a silver content in the range of about 25-70% silver to the surfaces and heating the surfaces with a torch until the brazing alloy flows; and thereafter discontinuing the heating of the surfaces before the nickel flows.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein the brazing alloy is applied in solid form to the surfaces prior to the initiation of the heating thereof.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein the ferrous powdered metal piece is a pipe flange and the other piece is an elongated metal pipe.
References Cited (Backward Citations)
GB380100A
Cited
US3222774A
Cited
US3380151A
Cited
US3409974A
Cited
US3744993A
Cited
US3851985A
Cited
US4029476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-01 | 1983-10-01 | 1984-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-01 | 1987-10-01 | 1988-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-01 | 1991-10-01 | 1992-04-01 | $7700.00 | Window Closed / Lapsed |