Described herein are compositions for use in the brazing of metal substrates. Methods of making and using these compositions are also described herein.

A flux composition includes a component (A) that is a powder of an alkali metal zinc fluoroaluminate represented by “M.sub.wZn.sub.xAl.sub.yF.sub.z (1)” (wherein M is K or Cs, and w, x, y, and z are a positive integer, the greatest common divisor of w, x, y, and z being 1), the content of the component (A) in the flux composition being 50 mass % or more. The flux composition prevents occurrence of a brazing defect and discoloration even when an aluminum alloy is brazed in an atmosphere having a high oxygen concentration, or an atmosphere having high humidity.

The disclosed method relates to manufacturing a heat exchanger which causes no brazing defects, and a heat exchanger manufactured by the method. The method relates to manufacturing a heat exchanger having an aluminum alloy tube defining a cooling-medium flowing passage and a copper alloy tube defining a water flowing passage, wherein a heat exchange is carried out between a cooling medium flowing through the cooling-medium flowing passage and water flowing through the water flowing passage. The aluminum alloy tube and the copper alloy tube are brazed to each other at a temperature of less than 548° C.

A method of ultrasonic additive manufacturing comprising using ultrasonic additive manufacturing to build a solid metal object through ultrasonically welding successive layers of thin metal foil into a three-dimensional shape; machining internal features into the solid metal object, wherein the internal features include voids, chambers, cavities, channels, or conduits; depositing a sacrificial support material in the internal features, wherein the sacrificial support material includes at least one water-soluble solid, and at least one water-soluble binding agent; curing the sacrificial support material at a predetermined temperature for a predetermined period of time within the internal features; using ultrasonic additive manufacturing to deposit additional successive layers of metal on top of the sacrificial material and solid metal object to complete the solid metal object; and introducing a solution containing water into the internal features to dissolve and remove the sacrificial support material therefrom.

A method for manufacturing a heat exchanger (1) includes joining an inner fin (3) to a hollow structure (20) formed from at least two clad plates (200a, 200b) by heating and brazing a filler metal layer (B). Each clad plate has a core layer (A) composed of an aluminum alloy that contains Mg: 0.40-1.0 mass %. The filler metal layer is composed of an aluminum alloy that contains Si: 4.0-13.0 mass %, and further contains Li: 0.0040-0.10 mass %, Be: 0.0040-0.10 mass %, and/or Bi: 0.01-0.30 mass %. The inner fin is composed of an aluminum alloy that contains Si: 0.30-0.70 mass % and Mg: 0.35-0.80 mass %. A flux (F) that contains cesium (Cs) is applied along a contact part (201), and the vicinity thereof, of the at least two clad plates prior to the heating. A heat exchanger (1) may be manufactured according to this method.

A solid metal flux comprised of compacted granules including (a) alkali chloride salt, (b) alkaline earth chloride salt and (c) at least one nitrate, carbonate, or sulfate salt and/or a fluoride containing salt.

The invention concerns a method for the manufacturing of a clad sheet product comprising a core layer (6) and at least one cladding layer, the method comprising rolling an assembly of a core layer and at least one cladding layer and reducing the thickness to a desired gauge, the core layer being made of an aluminium alloy, the at least one cladding layer comprising a centre section (2) and at least two edge sections (4, 5) positioned at opposite sides of the centre section (2) along the edges of the at least one cladding layer, the centre section being made of a material being an aluminium alloy or a composite material comprising a matrix of aluminium or an aluminium alloy, the edge sections along (4, 5) the edges being made of a material different from the material of the centre section, wherein the edge sections (4, 5) are cut off during or after the rolling. The invention further concerns a cladding plate useful in the method.

The invention concerns a brazing sheet comprising a core layer (5) and a braze cladding, said core layer (5) being aluminium or an aluminium alloy, said braze cladding comprising (a) a flux composite layer (2), which flux composite layer comprises a matrix of aluminium or an aluminium alloy, said matrix containing flux particles; (b) at least one filler alloy layer (1) not containing flux particles; and, (c) an aluminium or aluminium alloy layer (3) not containing flux particles, said layer forming the outermost surface of at least one side of the brazing sheet, wherein the flux composite layer (a) is positioned between said filler alloy layer (b) and said aluminium or aluminium alloy layer (c). The invention further concerns a method for its manufacturing, a cladding plate, use of the brazing sheet and a brazed heat exchanger.

The present invention relates to a metal paste including: a first metal powder including nickel (Ni); a second metal powder including at least one selected from the group consisting of tin (Sn), zinc (Zn), bismuth (Bi), and indium (In); and a dispersing agent, and to a thermoelectric module which adopts a bonding technique using the metal paste.

A method for manufacturing a heat exchanger (1) includes joining an inner fin (3) to a hollow structure (20) formed from at least two clad plates (200a, 200b) by heating and brazing a filler metal layer (B). Each clad plate has a core layer (A) composed of an aluminum alloy that contains Mg: 0.40-1.0 mass %. The filler metal layer is composed of an aluminum alloy that contains Si: 4.0-13.0 mass %, and further contains Li: 0.0040-0.10 mass %, Be: 0.0040-0.10 mass %, and/or Bi: 0.01-0.30 mass %. The inner fin is composed of an aluminum alloy that contains Si: 0.30-0.70 mass % and Mg: 0.35-0.80 mass %. A flux (F) that contains cesium (Cs) is applied along a contact part (201), and the vicinity thereof, of the at least two clad plates prior to the heating. A heat exchanger (1) may be manufactured according to this method.