Abstract: An aluminum alloy for microporous hollow shape material use constituted by an aluminum alloy which has excellent corrosion resistance and extrudability which keeps down the content of Cu which poses a problem in intergranular corrosion resistance, which maintains the natural potential noble, which adds transition metals which do not obstruct the extrudability is provided, that is, an aluminum alloy which has a chemical composition which contains, by mass %, Fe: 0.05 to 0.20%, Si: 0.10% or less, Cu: 0.15 to 0.32%, Mn: 0.08 to 0.15%, Zr: 0.05% or less, Ti: 0.06 to 0.15%, Cr: 0.03% or less, and balance: Al and unavoidable impurities and has an amount of gas in the alloy billet of 0.25 cc/100 g or less, and a method of production of an aluminum alloy which, produces a DC cast billet.

Abstract: An aluminum alloy for microporous hollow shape material use constituted by an aluminum alloy which has excellent corrosion resistance and extrudability which keeps down the content of Cu which poses a problem in intergranular corrosion resistance, which maintains the natural potential noble, which adds transition metals which do not obstruct the extrudability is provided, that is, an aluminum alloy which has a chemical composition which contains, by mass %, Fe: 0.05 to 0.20%, Si: 0.10% or less, Cu: 0.15 to 0.32%, Mn: 0.08 to 0.15%, Zr: 0.05% or less, Ti: 0.06 to 0.15%, Cr: 0.03% or less, and balance: Al and unavoidable impurities and has an amount of gas in the alloy billet of 0.25 cc/100 g or less, and a method of production of an aluminum alloy which, produces a DC cast billet.

Abstract: Provided as an aluminum alloy for finely hollow shapes is an aluminum alloy that is reduced in the content of Cu, which is problematic with respect to intergranular corrosion resistance, and that can be kept having a noble self-potential and has excellent extrudability. The alloy has a chemical composition which contains 0.05-0.15 mass % Fe, up to 0.10 mass % Si, 0.03-0.07 mass % Cu, 0.30-0.55 mass % Mn, 0.03-0.06 mass % Cr, and 0.08-0.12 mass % Ti and which optionally further contains up to 0.08 mass % V so as to satisfy the relationship Ti+V=0.08 to 0.2 mass %. Also provided is a process for producing a finely hollow aluminum alloy shape.

Abstract: By the use of a heat exchanger tube not required for adhesion of Zn in advance and a fin not clad with a brazing composition, a heat exchanger core is provided which has corrosion resistance and brazing capability comparable to or higher than those of the conventional counterpart. Applied onto an outer surface of an extruded flattened tube as a heat exchanger tube is a brazing composition derived from a mixture of silicon and fluorine type flux, and a fin formed of an aluminum-based zinc-containing material is prepared. The extruded flattened tube and the fin are then heated at a given temperature so that the same are brought into brazed relation to each other, and a mixed diffusion layer of silicon and zinc is then on the outer surface of the extruded flattened tube.

Abstract: A brazing material comprising a mixture of aluminum brazing powder (i.e. Si, Zn, Cu or Ge), flux, binder, and alcohol for diluting the binder is coated on a surface of an extruded flat tubed strip of aluminum type and this and aluminum type fins are brazed together.

Abstract: After immersing an extruded flat tubed strip, in an immersion tank containing a slurry of a brazing material having brazing metallic powder and brazing flux powder mixed in alcohol that has binder dissolved therein, the extruded flat tubed strip is pulled up virtually vertically. Furthermore, the slurry coated on the extruded flat tubed strip pulled up from the immersion tank is dried and bonded/baked on the extruded flat tubed strip through the drying means.