High-corrosion-resistant aluminum alloy brazing sheet, method of manufacturing such sheet, and corrosive-resistant heat exchanger using such sheet

摘要

An aluminum alloy brazing sheet having a good brazing property that prevents diffusion of molten filler material in a core material of the aluminum alloy brazing sheet during a brazing process and which has a superior corrosion resistance to an exhaust gas condensate water after the brazing process is disclosed. A method of manufacturing of the aluminum alloy brazing sheet also is disclosed. A high corrosion-resistant heat exchanger that employs the aluminum alloy brazing sheet also is disclosed.

主权项

1. A high corrosion-resistant aluminum alloy brazing sheet comprising:
a core material of comprising an aluminum alloy; a sacrificial anode material cladded on one surface of said core material; and a filler material comprising an Al/Si-based alloy and cladded on another surface of said core material, wherein said sacrificial anode material comprises an aluminum alloy which contains Si falling within a range of about 2.5-about 7.0 mass %, Zn falling a range of about 1.0-about 5.5 mass %, Fe falling within a range of about 0.05-about 1.0 mass %, and which comprises as balance Al and inevitable impurities, wherein a clad thickness of said sacrificial anode material falls within a range of about 25-about 80 μm and wherein a value (X) is determined by the following formula (1) is at most 150:
X=(1.1-0.1×Sic)×Znc×T  (1) wherein Sic (mass %) is a content of Si; Znc (mass %) is a content of Zn; and T (μm) is a clad thickness of said sacrificial anode material and wherein an existence density of Si particles having a projected area diameter of at least 1.0 μm is at most 5,000/mm2 in a matrix of said sacrificial anode material.