Aluminum pipe and process for producing same
AssigneeShowa Denko K.K.
InventorTeruki Morita
Life of this patent
Estimating the term…
Abstract
An inlet pipe 6 and an outlet pipe 7 for a condenser are made from an alloy containing 0.9 to 1.5 mass % of Mn, and the balance Al and inevitable impurities. Each of the inlet pipe 6 and the outlet pipe 7 contains Zn diffused through a surface layer portion thereof from the outermost surface of outer periphery of the pipe to a depth of at least 60 fÊm, and the surface layer portion has a Zn concentration of 0.20 to 0.70 mass %. The pipes 6 and 7 can be produced easily at a low cost and have satisfactory resistance to pitting corrosion.
Claims17
An aluminum pipe made from an alloy containing 0.9 to 1.5 mass % of Mn, and the balance Al and inevitable impurities, the pipe containing Zn diffused through a surface layer portion thereof from the outermost surface of an outer periphery of the pipe to a depth of at least 60 μm, the surface layer portion having a Zn concentration of 0.20 to 0.70 mass %.
A process for producing an aluminum pipe characterized in that a pipe blank made from an alloy containing 0.9 to 1.5 mass % of Mn, and the balance Al and inevitable impurities, and an aluminum material having 2.0 to 16.0 g/m2 of a Zn spray layer formed over a surface thereof and 75 to 600 g in total amount of Zn are heated at 580 to 610° C. for 3 to 15 minutes in a furnace having an inert gas atmosphere.
Dependencies are inferred from the claim text.