Abstract: An aluminum alloy brazing sheet used for brazing aluminum, without using a flux, in an inert gas atmosphere or vacuum is formed by arranging a brazing material on one side or both sides of a core material made of pure aluminum or aluminum alloy, the brazing material including 6% to 13% by mass of Si and the balance being Al and inevitable impurities, and performing cladding with an intermediate material interposed between the core material and the brazing material, the intermediate material including 0.01% to 1.5% by mass of Bi, 1.5% to 13% by mass of Si, and the balance being Al and inevitable impurities, the intermediate material having a thickness of 2% to 35% of a thickness of the brazing material, wherein one or both of the intermediate material and the core material includes 0.4% to 6% by mass of Mg.

Abstract: A brazing sheet used for brazing aluminum in an inert gas atmosphere or vacuum is formed by arranging a brazing material on one side or both sides of a core material made of pure aluminum or aluminum alloy, and performing cladding with an intermediate material interposed between the core material and the brazing material. The brazing material includes 6% to 13% of Si and the balance being Al and inevitable impurities. The intermediate material includes 0.01% to 1.5% of Bi, at least one of 0.05% or more of Li, 0.05% or more of Be, 0.05% or more of Ba, and 0.05% or more of Ca, and the balance being Al and inevitable impurities. By promptly supplying Bi and Li, Be, Ca, and/or Mg into the brazing material during brazing heating, these elements are eluted in the molten brazing material, embrittling the oxide film on the surface of the brazing material.

Abstract: An aluminum alloy brazing sheet makes it possible to inexpensively braze aluminum in a nitrogen gas furnace without using flux and a toxic element. The aluminum alloy brazing sheet is used for brazing aluminum in an inert gas atmosphere without using flux, and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, and the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities.

Abstract: A brazing method includes shaping a clad plate to form a hollow structure. The clad plate has at least one layer containing an element that breaks down an oxide film when heated. A tube is then partially inserted into a through hole in the hollow structure, thereby forming an assembled aluminum structure. The exterior surface of the hollow structure adjacent the through hole is composed of an Al—Si alloy that serves as a filler-material layer. The exterior surface of the tube that opposes the through hole of the hollow structure is composed of aluminum or an aluminum alloy that does not function as a filler when brazed. The assembled aluminum structure is brazed by heating it and then cooling it in an inert-gas atmosphere such that the filler-material layer of the clad plate flows and forms a fillet joining the hollow structure to the tube along the through hole.

Abstract: An aluminum heat exchanger is made by disposing an inner fin in a closed space formed by overlapping edge portions of a formed single tube plate or a plurality of formed tube plates, and brazing a first joint obtained by overlapping the edge portions of the tube plate and a second joint obtained by causing the inner fin to abut against the tube plate, wherein an Al—Si-based brazing filler material is interposed at the first and second joints, and brazing is carried out in an inert gas atmosphere without using flux, wherein the inner fin is constituted of a brazing sheet obtained by cladding a core material of an aluminum alloy, on both surfaces thereof, with the Al—Si-based brazing filler material having a solidus temperature of 570° C. or lower, the solidus temperature being lower than a solidus temperature of the Al—Si-based brazing filler material interposed at the first joint.

Abstract: An aluminum alloy brazing sheet makes it possible to inexpensively braze aluminum in a nitrogen gas furnace without using flux and a toxic element. The aluminum alloy brazing sheet is used for brazing aluminum in an inert gas atmosphere without using flux, and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, and the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities.

Abstract: A hollow aluminum structure that will be brazed includes at least one brazing sheet having a filler metal layer clad onto a core layer. The core layer is composed of aluminum or an aluminum alloy containing less than 0.2 mass % Mg. The filler metal layer is composed of an aluminum alloy that contains Si: 4.0-13.0 mass % and Bi: 0.01-0.3 mass %, and further contains Li: 0.004-0.08 mass % and/or Be: 0.006-0.12 mass %, the filler metal layer containing less than 0.1 mass % Mg. The hollow aluminum structure is assembled such that the filler metal layer is present at locations that will form both an interior-facing brazed joint and an exterior-facing brazed joint. Then, flux is applied onto the filler metal layer at the location that will form the exterior brazed joint, and the hollow aluminum structure heated in an inert gas atmosphere to form the interior brazed joint and the exterior brazed joint.

Abstract: An aluminum alloy brazing sheet exhibits excellent brazability by effectively weakening an oxide film formed on the surface of a filler metal. The aluminum alloy brazing sheet includes a core material and a filler metal, and is used to braze aluminum in an inert gas atmosphere or in vacuum, the core material including aluminum or an aluminum alloy, the filler metal including 6 to 13 mass % of Si, with the balance being Al and unavoidable impurities, and one side or each side of the core material being clad with the filler metal, wherein the core material is clad with the filler metal in a state in which a sheet material is interposed between the core material and the filler metal, the sheet material including one element, or two or more elements, among 0.05 mass % or more of Li, 0.05 mass % or more of Be, 0.05 mass % or more of Ba, and 0.05 mass % or more of Ca, with the balance being Al and unavoidable impurities.

Abstract: A brazing furnace (1) includes a preheating chamber (2) and a brazing chamber (3). The preheating chamber (2) includes: a vacuum pump (21) for reducing the pressure inside the preheating chamber (2) while a material to be processed (100) is housed therein; a preheating apparatus (22), which preheats the material to be processed (100) in a reduced-pressure atmosphere; and a gas introducing apparatus (23), which introduces inert gas into the preheating chamber (2) to restore the pressure inside the preheating chamber (2) after the preheating. The brazing chamber (3) includes: a gas-replacing apparatus (31), which introduces inert gas into the brazing chamber (3); and a main heating apparatus (32), which heats the material to be processed (100) to a brazing temperature while it is housed in the brazing chamber (3).

Abstract: An aluminum clad member is produced by: disposing a joining assistance member at a joint interface between an Al core member and an Al skin member, which joining assistance member being formed by crossing Al wires with each other in longitudinal and lateral directions to form a grid, and having a structure in which spot-like thick portions having a thickness of 0.2-3.2 mm are formed at intersections of the Al wires and arranged in the longitudinal and lateral directions so as to be spaced apart from each other by a distance of 0.2-13 mm; and performing a hot rolling operation with respect to the thus obtained stack of the Al core member, the Al skin member and the joining assistance member, by partially fixing together those members at their peripheral portions or without fixing together those members, such that the joint interfaces is communicated with an ambient air.

Abstract: A brazing sheet for brazing in an inert-gas atmosphere without using a flux has a core and a filler material clad to one side or both sides of the core. The core has a chemical composition that contains Mg: 0.35-0.8% (mass %; likewise hereinbelow), the remainder being composed of Al and unavoidable impurities. The filler material has a chemical composition that contains Si: 6-13% and Bi: 0.001-0.05% and Mg: limited less than 0.05%, the remainder being composed of Al and unavoidable impurities.

Abstract: An aluminum alloy brazing sheet achieves a stable brazability equal to by brazing using a flux, even if an etching treatment is not performed on the brazing site. The aluminum alloy brazing sheet is used to braze aluminum in an inert gas atmosphere without using a flux and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities, a surface oxide film having been removed from the brazing sheet, and an oil solution that decomposes when heated at 380° C. or less in an inert gas having been applied to the brazing sheet.

Abstract: An aluminum alloy brazing sheet achieves a stable brazability equal to by brazing using a flux, even if an etching treatment is not performed on the brazing site. The aluminum alloy brazing sheet is used to braze aluminum in an inert gas atmosphere without using a flux and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities, a surface oxide film having been removed from the brazing sheet, and an oil solution that decomposes when heated at 380° C. or less in an inert gas having been applied to the brazing sheet.

Abstract: An aluminum alloy heat exchanger is produced by applying a coating material that is prepared by adding a binder to a mixture of an Si powder and a Zn-containing compound flux powder to a surface of an aluminum alloy refrigerant tube, assembling a bare fin that is formed of an Al—Mn—Zn alloy with the refrigerant tube, and brazing the refrigerant tube and the bare fin by heating in an atmosphere-controlled furnace, the refrigerant tube being an extruded product of an aluminum alloy that comprises 0.5 to 1.7% (mass %, hereinafter the same) of Mn, less than 0.10% of Cu, and less than 0.10% of Si, with the balance being Al and unavoidable impurities.

Abstract: An aluminum clad member is produced by: disposing a joining assistance member at a joint interface between an Al core member and an Al skin member, which joining assistance member being formed by crossing Al wires with each other in longitudinal and lateral directions to form a grid, and having a structure in which spot-like thick portions having a thickness of 0.2-3.2 mm are formed at intersections of the Al wires and arranged in the longitudinal and lateral directions so as to be spaced apart from each other by a distance of 0.2-13 mm; and performing a hot rolling operation with respect to the thus obtained stack of the Al core member, the Al skin member and the joining assistance member, by partially fixing together those members at their peripheral portions or without fixing together those members, such that the joint interfaces is communicated with an ambient air.

Abstract: An aluminum alloy heat exchanger is produced by applying a coating material that is prepared by adding a binder to a mixture of an Si powder and a Zn-containing compound flux powder to a surface of an aluminum alloy refrigerant tube, assembling a bare fin that is formed of an Al—Mn—Zn alloy with the refrigerant tube, and brazing the refrigerant tube and the bare fin by heating in an atmosphere-controlled furnace, the refrigerant tube being an extruded product of an aluminum alloy that comprises 0.5 to 1.7% (mass %, hereinafter the same) of Mn, less than 0.10% of Cu, and less than 0.

Abstract: In a method for brazing a sheet material without use of flux, an inert gas is firstly introduced into an oxygen pump to reduce an oxygen partial pressure in the inert gas to 1×10?10 Pa or less, and the sheet material is heated in a brazing furnace in an atmosphere of the inert gas discharged from the oxygen pump. A core alloy of the sheet material or a brazing filler alloy cladded to a surface of the core alloy contains Mg. Both the core alloy and the brazing filler alloy may contain Mg. Accordingly, brazability of the sheet material is sufficiently improved.

Abstract: An aluminum alloy brazing sheet makes it possible to inexpensively braze aluminum in a nitrogen gas furnace without using flux and a toxic element. The aluminum alloy brazing sheet is used for brazing aluminum in an inert gas atmosphere without using flux, and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, and the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities.

Abstract: An aluminum alloy brazing sheet makes it possible to inexpensively braze aluminum in a nitrogen gas furnace without using flux and a toxic element. The aluminum alloy brazing sheet is used for brazing aluminum in an inert gas atmosphere without using flux, and includes a core material and a filler metal, one side or each side of the core material being clad with the filler metal, the core material being formed of an aluminum alloy that includes 0.2 to 1.3 mass % of Mg, and the filler metal including 6 to 13 mass % of Si and 0.004 to 0.1 mass % of Li, with the balance being aluminum and unavoidable impurities.

Abstract: An aluminum alloy clad sheet for heat exchangers includes a core material, a cladding material 1, and a cladding material 2, one side and the other side of the core material being respectively clad with the cladding material 1 and the cladding material 2, the core material containing 0.5 to 1.2% of Si, 0.2 to 1.0% of Cu, 1.0 to 1.8% of Mn, and 0.05 to 0.3% of Ti, with the balance being Al and unavoidable impurities, the cladding material 1 containing 3 to 6% of Si, 2 to 8% of Zn, and at least one of 0.3 to 1.8% of Mn and 0.05 to 0.3% of Ti, with the balance being Al and unavoidable impurities, and the cladding material 2 containing 6 to 13% of Si, with the balance being Al and unavoidable impurities, the cladding material 1 serving as the outer side of the aluminum alloy clad sheet during use.