Claims
- 1. A composite shape suitable for use in the manufacture of heat exchangers, said shape comprising an aluminum or aluminum alloy core formed by a process in which the surface of the core which is formed is substantially free of oxide, and an outer layer of fluxless soldering material of zinc or zinc base alloy which has been deposited on the said aluminum core in a thickness sufficient for acting as a fluxless solder in a subsequent operation of joining the core to another member, the deposition having been carried out with the soldering material in a molten state while the metal of the core is in a nascent state such that a portion only of the soldering material which is toward the core surface is diffused into the aluminum core, thereby interbonding the soldering material to the aluminum core.
- 2. A composite shape as claimed in claim 8, wherein said core is an extruded hollow shape.
- 3. A composite shape as claimed in claim 8, wherein said core is a drawn hollow shape which has been subsequently heated up to a temperature equal to or higher than the melting point of the soldering material.
- 4. A composite shape as claimed in claim 1, wherein the entire surface of said core is covered by the soldering material.
- 5. A method of making a composite shape suitable for use in the manufacture of heat exchangers, said method comprising forming an aluminum or aluminum alloy core by a process in which the core surface in a nascent state is kept substantially free of oxide, and depositing an outer layer of fluxless soldering material of zinc or zinc base alloy on said surface of the core in a molten state while the metal of said surface is in the nascent state, to cause a portion the soldering material to diffuse into the aluminum core for interbonding the soldering material to the aluminum core, and the depositing being in a thickness sufficient for acting as a fluxless solder in a subsequent operation of joining the core to another member.
- 6. A method as claimed in claim 5, wherein said forming of the core is by a continuous forming process, and said outer layer is formed by a continuous deposition process in line with said forming process.
- 7. A method as claimed in claim 6, wherein said forming of the core comprises extruding a hollow shape.
- 8. A method as claimed in claim 6, wherein said forming of the core comprises drawing a hollow shape and subsequently heating it up to a temperature equal to or higher than the melting point of the soldering material.
- 9. A method as claimed in claim 5, wherein the soldering material is deposited at a temperature above the melting point of the soldering material and up to 840.degree. F.
- 10. A method as claimed in claim 5, wherein said depositing comprises deposition soldering material on the entire suface of said core.
Parent Case Info
This application is a continuation application of Ser. No. 570,845, filed Jan. 16, 1984 now U.S. Pat. No. 4,615,952, which is a continuation-in-part of application Ser. No. 437,884, filed Oct. 29, 1982, now abandoned.
US Referenced Citations (24)
Foreign Referenced Citations (9)
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JPX |
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JPX |
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Non-Patent Literature Citations (2)
Entry |
"ZD Aluminum Tube", Showa Aluminum K.K., pp. 1-16. |
"The Soldering of Sheet-Metal Heat Exchangers", M. K. Forbes, The Manufacture of Vehicle and Industrial Radiators, Apr. 1965, pp. 31-44. |
Continuations (1)
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Number |
Date |
Country |
Parent |
570845 |
Jan 1984 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
437884 |
Oct 1982 |
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