US5094700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solder and brazing alloys having improved properties and method of preparation
Assignee: CINCINNATI A CORP OF OH, University of
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Filing: 1990-03-22
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Granted: 1992-03-10
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Expires: 2010-03-22
Abstract
Abstract A solder or brazing alloy having improved properties by reason of the presence of at least one uniformly dispersed non-acicular and non-dendritic intermetallic phase having a particle size of about 1 to 25 microns. A method of preparing the alloy comprises melting the alloy at a temperature sufficient to melt the intermetallic phase or phases, cooling to a semi-solid state, subjecting the semi-solid alloy to vigorous shearing and/or vibration at the solid-liquid interface, and solidifying the alloy.
Inventors
- 👤 Jainagesh A. Sekhar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:11
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; C; C22; C22C; C22C1/00; C22C1/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
103 words
A method of improving the properties of solder and brazing alloys which contain at least one coarse, acicular and/or dendritic intermetallic phase having a higher melting temperature than that of the matrix alloy, which comprises melting said solder or brazing alloy at a temperature sufficient to melt said at least one intermetallic phase, cooling said alloy to a semi-solid state, subjecting the semi-solid alloy to vigorous shearing and/or vibration at the solid-liquid interface while in said semi-solid state, and solidifying said alloy whereby to obtain a microstructure wherein said at least one intermetallic phase is present as a fine, non-acicular and non-dendritic structure.
Claim 2
Independent Claim
103 words
A method of improving the properties of solder and brazing alloys which contain at least one coarse, acicular and/or dendritic intermetallic phase having a higher melting temperature than that of the matrix alloy, which comprises melting said solder or brazing alloy at a temperature sufficient to melt said at least one intermetallic phase, cooling said alloy to a semi-solid state, subjecting the semi-solid alloy to vigorous shearing and/or vibration at the solid-liquid interface while in said semi-solid state, and solidifying said alloy whereby to obtain a microstructure wherein said at least one intermetallic phase is present as a fine, non-acicular and non-dendritic structure.
Claim 3
Dependent Claim
29 words
The method of claim 1, wherein said vigorous shearing involves an amount of shear greater than 1000% and a rate of shear greater than 0.5 to 1 mm/mm sec.
Claim 4
Dependent Claim
26 words
The method of claim 1, wherein said alloy is chosen from the group consisting of tin--copper, silver--copper--phosphorus, silver--zinc, silver--tin, silver--copper--tin, tin--antimony, silicon--aluminum, magnesium--aluminum, indium--tin, and bismuth--lead.
Claim 5
Dependent Claim
43 words
A solder alloy containing at least one intermetallic phase, produced by the method of claim 1, wherein said at least one intermetallic phase is in the form of uniformly dispersed non-acicular and non-dendritic particles having a size of about 1 to 25 microns.
Claim 6
Dependent Claim
36 words
The method of claim 3, wherein said alloy is a tin--copper system containing about 4% copper and balance tin aside from incidental impurities, and wherein said alloy is melted at a temperature above about 415° C.
Claim 7
Dependent Claim
37 words
The method of claim 3, wherein said alloy is a tin--silver system containing about 10% silver and balance tin aside from incidental impurities, and wherein said alloy is melted at a temperature of at least 310° C.
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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) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-10 | 2003-09-09 | 2004-03-10 | $7700.00 | Window Closed / Lapsed |