| 摘要 |
1,160,655. Brazing. ALUMINUM CO. OF AMERICA. 19 June, 1967 [24 June, 1966] No. 28265/67. Heading B3R. In a method of joining aluminium members by furnace brazing, at least one of the members is provided at the joint with a small quantity of aluminium brazing alkali metal halide salt flux, the members are brought into joint relationship with an aluminium brazing filler metal in an atmosphere having a dew point of 40‹ F. or lower, and then brazing is carried out. The flux is immersion depositable from an aqueous solution containing not more than 15% flux, and preferably between 1¢% and 7%. The dew point of the brazing atmosphere is preferably between minus 10‹ F. and minus 100‹ F. The flux comprises mixtures of the halides, mainly chlorides and fluorides of alkali metals, although they may include small amounts of one or more other salts such as the halides of aluminium, zinc, the alkaline earth, and some heavy metals. The brazing atmosphere may be air, nitrogen, pure oxygen, or argon. The filler may be of wire, shims, wire ring or sheet form, and may be of an aluminium alloy consisting of a cladding containing 7À5%- 10% silicon, and a core of Al, and 1.2% Mn, or an alloy of Al, 0.25% Cu, 0.35% Si, 0À65% Mg. The joining can be performed continuously by providing a cleaning and assembling station, flux coating in an immersion bath station, a brazing station, and a residual flux removal a drying station or rinsing station. |
