Method for preparing flexible welding wire of brittle aluminum-silicon-copper brazing filler metal

Abstract

The invention discloses a method for preparing a flexible welding wire of a brittle aluminum-silicon-copper brazing filler metal. The method is characterized in that a mixed powder is wrapped by a flexible material aluminum-silicon alloy skin, wherein the mixed powder is prepared from, by weight, 10%-100% of brittle material aluminum-silicon copper powder and 0%-90% of aluminum brazing agent powder. The method comprises the steps that the aluminum-silicon copper powder is prepared from the aluminum-silicon-copper brazing filler metal by a vacuum smelting gas atomization method; the aluminum-silicon copper powder and the aluminum brazing agent powder are mixed according to a weight ratio, and are placed in a double-planetary stirrer for full stirring, and the mixed powder is obtained; an aluminum-silicon brazing filler metal is subjected to smelting, extruding, rolling and slitting to obtain an aluminum-silicon brazing filler metal strip; and the aluminum-silicon brazing filler metal strip is put into a welding wire forming machine, sequentially passes through each roller, and finally is rolled into a tubular welding wire, and the tubular welding wire is stored in a winding machine.During the wire forming process, the mixed powder is added through a powder feeder, and the flexible tubular flux-cored wire is obtained by winding. According to the method, the problem of poor processing forming performance caused by the large brittleness of the aluminum-silicon-copper brazing filler metal is solved.

Description

technical field [0001] The invention relates to a method for preparing a flexible welding wire of brittle aluminum-silicon-copper solder. Background technique [0002] Aluminum alloys are widely used in industrial production and social life. Due to their small specific gravity, good electrical and thermal conductivity, excellent castability, plasticity and machining properties, aluminum alloys play an irreplaceable role in modern industrial materials. The use of 3-series and 6-series high-strength aluminum alloys to make parts to replace the original copper structural parts has become the development direction of the world's manufacturing industry. However, there are more and more welding problems of copper-aluminum components. [0003] At present, zinc-aluminum solder, aluminum-silicon solder or aluminum-silicon-copper solder is mostly used for brazing connection of copper-aluminum components, but there are some shortcomings. When welding copper-aluminum components with z...

AI Technical Summary

Problems solved by technology

When welding copper-aluminum components with zinc-aluminum solder, electrochemical corrosion is prone to occur at the welding joint position, and the service life is short; the melting point of aluminum-silicon solder is relatively high, the solidus temperature is 577 ° C, and the liquidus line is above 600 ° C. The melting points of 3-series and 6-series high-strength aluminum alloys are very close, and they are very easy to overheat during brazing; the welded joints of aluminum-silicon-copper solder have good corrosion resistance, but the solder itself is brittle and has poor processability, and it is difficult to process the solder into coils. Shaped welding wire or welding ring, unable to achieve continuous automation and high-efficiency brazing requirements