Self-fluxing brazing filler metal and preparation method thereof

Abstract

The invention relates to self-fluxing brazing filler metal and a preparation method thereof. The self-fluxing brazing filler metal comprises a porous body formed by sintering an alloy and a welding flux in the holes in the porous body. The preparation method comprises the following steps: (1) preparing atomizing alloy powder; (2) uniformly mixing 93 to 97 weight parts of the atomizing alloy powder with 3 to 7 weight percent of ammonium hydrogen carbonate to obtain mixture, and processing the mixture into a blank piece; (3) sintering the blank piece to form the porous body with the holes; (4) placing the welding flux into the holes in the porous body; (5) placing the porous body obtained in the step (4) into a lukewarm water tank to remove excessive welding flux on the surface of the porous body, drying to remove moisture, and packaging. As the preparation method adopts powder metallurgy, and sintering is carried out after mechanical extrusion or pressing is conducted on alloy powder, the problem that moderate-temperature brazing filler metal is difficult to be processed into forms in the prior art is solved. Moreover, as the molten welding flux is soaked into a porous workpiece through dipping, an operator is prevented from being in touch with the welding flux, harm to the body of the operator is reduced, the labor intensity is greatly reduced, and convenience is brought for popularization.

Description

technical field [0001] The invention relates to a self-brazing solder and a preparation method thereof, in particular to a self-brazing solder with excellent performance prepared by adopting a powder metallurgy porous body combined with an impregnation method and a preparation method thereof. Background technique [0002] At present, cold steel companies basically use 20%-45% silver-based solder for the connection of steel pipes. This type of solder has good fluidity and moderate melting point, which can better meet the rhythm and quality assurance required by production capacity. . However, due to the relatively high content of the precious metal silver, the manufacturing cost of this type of solder is very high. If the silver content is reduced or even does not contain silver, the performance of the solder will deteriorate, and the main melting point will increase. If you don’t pay attention, it will burn out. For pipelines, if the melting point is forcibly lowered and th...

AI Technical Summary

Problems solved by technology

The brazing flux is mainly composed of fluoride, which is easy to float in the working environment in the form of dust when used, and the health of the operators and the pollution of the environment cannot be ignored.

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