Claims
- 1. A coiled composite sheet material for brazing, the composite sheet material having a structure comprising a substrate, selected from the group consisting of an aluminium substrate and aluminium alloy substrate, on at least one side coupled to a carrier layer having a thickness of at most 150 μm and comprising a polymer selected from the group consisting of homopolymers of olefin, and a copolymer of an olefin and a non-olefinic comonomer copolymerizable with the olefin selected from at least one member of the group consisting of vinyl monomer, acrylic acid, methacrylic acid and acetic acid as a carrier filled with a brazing flux material,
said brazing flux material comprising at least one member of the group consisting of a fluoride flux and a chloride flux in an amount sufficient to achieve brazing, and the brazing flux material has an average particle size dimension of less than 5 μm and the amount of brazing flux material per side of the composite sheet material is less than 5 gram/m2 and is arranged substantially homogeneously throughout the carrier layer and the thickness of the filled carrier layer is substantially the same over the whole surface area covered.
- 2. A composite sheet material for brazing according to claim 1, wherein the carrier layer comprises the polymer as the carrier filled with both the brazing flux material and a metal powder, in an amount sufficient to achieve brazing.
- 3. A composite sheet material in accordance with claim 1, wherein said metal substrate is coupled to the filled polymer carrier via a layer of filler metal.
- 4. A composite sheet material in accordance with claim 1, wherein the carrier layer has a thickness of at most 50 μm, and covers substantially the whole surface area of at least one side of the aluminium or aluminium alloy substrate.
- 5. A composite sheet material in accordance with claim 1, wherein the brazing flux material in combination with metal powder, are arranged substantially homogeneously throughout the carrier layer.
- 6. A composite sheet material in accordance with claim 1, wherein the brazing flux material has an average particle size dimension of less than 2 μm.
- 7. A composite sheet material in accordance with claim 1, wherein the amount of brazing flux material per side of the composite sheet material is less than 3 gram/m2.
- 8. A composite sheet material in accordance with claim 1, wherein said carrier layer is at least filled with said brazing flux material and a metal powder selected from the group consisting of: aluminium, silicon, aluminium-silicon alloy, zinc, zinc-aluminium alloy, magnesium, aluminium-magnesium alloy, magnesium- zinc alloy, aluminium-zinc alloy, copper, copper alloy, nickel, titanium, silver, indium, lead, germanium, bismuth, strontium and tin.
- 9. A composite sheet material in accordance with claim 1, wherein said carrier is at least filled with a metal powder selected from the group consisting of metal powder having a corrosion potential different from that of the underlying metal substrate, and metal powder having a corrosion potential lower than that of the underlying metal substrate.
- 10. A method of use of a sheet of a composite sheet material as defined in claim 1, comprising brazing said sheet to another component of an assembly.
- 11. A method of use of a sheet of a composite sheet material as defined in claim 2, comprising brazing said sheet to another component of an assembly.
- 12. A method of use of a sheet of a composite sheet material as defined in claim 7, comprising brazing said sheet to another component of an assembly.
- 13. A method of use of a sheet of a composite sheet material as defined in claim 9, comprising brazing said sheet to another component of an assembly.
- 14. A method of manufacturing composite sheet material for brazing in accordance with claim 1, which comprises
(a) mixing the polymer with the brazing flux material in the absence of a solvent for the polymer, and (b) applying to at least one side of the metal substrate a mixture of the polymer filled with the brazing flux material, in an amount sufficient to achieve subsequent brazing.
- 15. A brazed assembly comprising at least one component of the composite sheet material of claim 1.
- 16. A brazed assembly according to claim 15, which has been brazed using a controlled atmosphere (CAB) process.
- 17. A brazed assembly according to claim 15, which has at least one internal brazed surface.
- 18. A composite sheet material in accordance with claim 1, wherein at least one said carrier layer is filled with both said brazing flux material and metal powder.
- 19. A composite sheet material in accordance with claim 1, wherein the carrier layer has a thickness of at most 10 μm, and covers substantially the whole surface area of at least one side of the aluminium or aluminium alloy substrate.
- 20. A composite sheet material in accordance with claim 2, wherein the metal powder particles range in size up to 60 μm.
- 21. A composite sheet material in accordance with claim 2, wherein the metal powder particles range in size up to 10 μm.
- 22. A brazed assembly comprising at least one component of the composite sheet material in accordance with claim 14.
- 23. A composite sheet material in accordance with claim 1, wherein the olefin comprises ethylene.
- 24. A composite sheet material in accordance with claim 23, wherein the polymer is polyethylene.
- 25. A composite sheet material in accordance with claim 23, wherein the polymer is a copolymer of ethylene and at least one member of the group consisting of acrylic acid and methacrylic acid.
- 26. A method of use of a sheet of a composite sheet material as defined in claim 23, comprising brazing said sheet to another component of an assembly.
- 27. A method of use of a sheet of a composite sheet material as defined in claim 25, comprising brazing said sheet to another component of an assembly.
- 28. A composite sheet material in accordance with claim 1, wherein the polymer is modified with unsaturated carboxylic acid or an anhydride, ester or metal salt thereof.
- 29. A composite sheet material in accordance with claim 27, wherein the unsaturated carboxylic acid is selected from the group consisting of maleic acid and fumaric acid or an anhydride, ester or metal salt thereof.
- 30. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises ethylene ethyl acrylate copolymer, ethylene/butyl acrylate copolymer, methylene/methacrylic acid copolymer and ionomer resin.
- 31. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises copolymer of ethylene and acrylic acid.
- 32. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises copolymer of ethylene and methacrylic acid.
- 33. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises maleic acid modified polyethylene.
- 34. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises polyethylenevinylacetate copolymer.
- 35. A composite sheet material in accordance with claim 1, wherein the polymer carrier layer comprises a member selected from the group consisting of low density polyethylene, very low density polyethylene and ultra low density polyethylene.
- 36. A composite sheet material in accordance with claim 1, wherein the polymer is selected such that, after Thermal Gravimetric Analysis to a temperature where weight decrease becomes zero, the polymer has a residual weight of at most about 0.2 weight percent.
- 37. A composite sheet material in accordance with claim 1, wherein the metal substrate comprises a member of the group consisting of Aluminium Association 3xxx, 5xxx, and 6xxx series aluminium alloys.
- 38. A composite sheet material in accordance with claim 1, wherein the carrier layer comprises the brazing flux material and a metal powder having a corrosion potential lower than that of the underlying metal substrate.
- 39. A composite sheet material in accordance with claim 1, wherein the carrier layer has a thickness of at most 5 μm, and covers substantially the whole surface area of at least one side of the aluminium or aluminium alloy substrate.
- 40. A method of manufacturing a brazed assembly using a sheet of the composite sheet material of claim 1, comprising the steps of:
(a) forming parts of which at least one is made of the composite sheet material; (b) assembling the parts into the assembly; (c) brazing the assembly in an CAB brazing operation to achieve brazing; and (d) cooling the brazed assembly to below 100° C. with a cooling rate of at least 20° C./min.
Priority Claims (1)
Number |
Date |
Country |
Kind |
99201232.8 |
Apr 1999 |
EP |
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a continuation-in-part of U.S. patent application Ser. No. 09/959,195 filed Jan. 24, 2002, incorporated herein by reference in its entirety, which is the National phase under 35 USC 371 of Patent Cooperation Treaty application no, PCT/EPOO/03753 having an International filing date of Apr. 21, 2000.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09959195 |
Jan 2002 |
US |
Child |
10841538 |
May 2004 |
US |