| 摘要 |
PURPOSE:To manufacture an aluminium heat exchanger of good solderability and corrosion resistance, by attaching aqueous solution of flux containing Zn compound to an assembled body made of aluminium and brazing filler metal and heat treating in the low dew point air atmosphere. CONSTITUTION:A part constituted of a clad plate consisting of core material made of aluminium or aluminium alloy and skin material that forms brazing filler metal and a part made of aluminium alloy are installed in the structure of a heat exchanger. Then, aqueous solution of flux containing 15-30%, desirably 17-20%, Zn compound, 15-45%, desirably 32-40%, in concentration is attached to the assembled body. This assembled body is put in a heating furnace that supplies dehydrated air of low dew point, desirably below -5 deg.C. Each parts are brazed, and at the same time, Zn in the flux is diffused, and a diffused layer of An is formed on the surface layer of aluminium base metal. |
