| 摘要 |
PURPOSE:To improve the corrosion resistance of the heat exchanger made of Al by using a brazing alloy contg. Si, Fe and Ti respectively at specific ratios and consisting of the balance Al and cladding the alloy to a core material which is electrochemically nobler than this alloy. CONSTITUTION:The brazing alloy for Al contg., by weight, 5-13% Si, 0.05-1.0% Fe and 0.06-0.3% Ti, and the balance Al and unavoidable impurities is prepd. The brazing alloy is then clad to both surfaces or one surface of the alloy core material contg. 0.5-1.5% Mn, 0.3-1.0% Cu, 0.1-0.7% Fe, 0.03-0.4% Si, and contg. 1 or 2 kinds of either of 0.05-0.3% Cr and 0.05-0.3% Zr at need to form the brazing sheet for the heat exchanger. The brazing filler metal is converted to the metal which is electrochemically base to the core material in this way so that the brazing filler metal plays the role of a sacrificial anode on the core material. The corrosion resistance of the heat exchanger is, therefore, improved. |
