Multi-silver brazing filler metal containing manganese and tin and preparation method thereof

Abstract

The invention relates to a multi-silver brazing filler metal containing manganese and tin, which consists of Ag, Cu, Sn, Mn, Ni and Zn, wherein the weight percentages of all the components are as follows: 19-22.5 wt% of Ag, 28-36 wt% of Zn, 36-40 wt% of Cu, 1.0-3.0 wt% of Sn, 3.5-6.5 wt% of Mn, 0.5-2.0 wt% of Ni, and 0.01-0.3 wt% of microelement R; and the microelement R is one of lanthanum, cerium and silicon, or consists of more than one of the three. The invention further comprises a preparation method of the multi-silver brazing filler metal; a medium-frequency smelting furnace is adopted to smelt and cast; all the components are added for smelting according to the sequence of Ag, Cu, Ni, Sn, Mn, Zn and Cu-R alloy; and then, the multi-silver brazing filler metal is prepared through casting, saw stripping, extrusion, drawing, molding and cleaning processes. Compared with the prior art, the multi-silver brazing filler metal has the following advantages and effects: (1) the multi-silver brazing filler metal can be used for replacing BAg45CuZnCd and Bag45CuZnCd silver brazing filler metals; the silver content is obviously reduced; the performance index parameters are approximate to that of BAg45CuZnCd and Bag45CuZnCd; and the cost performance is excellent; (2) when red copper, brass and stainless steel are brazed, the mechanical performance is excellent; (3) the brazing filler metal is better in processing plasticity; and (4) the product melting temperature is 700-770 DEG C.

Description

technical field [0001] The invention relates to a multi-component silver brazing material containing manganese, tin and other elements and a preparation method thereof, which is suitable for brazing stainless steel and copper alloys such as copper and brass, and belongs to a medium-temperature brazing material. Background technique [0002] When brazing copper and copper alloys with ferrous metals such as iron and their alloys, considering the wettability of the brazing material to the brazing base material and the mechanical properties of the brazed joint, most people choose silver solder. For example, the common BAg45CuZnCd and BAg45CuZn are widely used in brazing copper, brass and stainless steel, with low melting temperature and low energy consumption in the brazing process. However, as the price of precious metal raw materials continues to rise, manufacturers who use high-silver solder for brazing are facing huge cost pressures. However, if the silver content of the so...

AI Technical Summary

Problems solved by technology

[0003] Some companies reduce the silver content by increasing the content of Cd. The addition of Cd greatly reduces the melting temperature of the solder, improves the brazing performance, and reduces the silver content. It was once widely tested, but Cd itself is Toxic elements are not conducive to the health of operators and pollute the environment. They do not comply with the EU RoHS directive. As people pay more and more attention to environmental protection, they are gradually replaced by other harmless elements.

[0004] According to the existing research results, the addition of other single elements is not enough to compare with Cd. For example, the addition of Sn in Ag-Cu-Zn-Sn solder can effectively improve fluidity and wettability, and reduce solid and liquidus. Temperature, reducing the melting range, but its machinability is often poor; the addition of In in the Ag-Cu-Zn-In solder can reduce the solidus and liquidus temperatures, reduce the melting range, and improve fluidity, but its own The solid solubility in silver and copper is small and the price is high; people began to focus on the development of silver solders with multi-alloy systems to replace the use of cadmium-containing silver solders

However, the addition of multi-elements is often due to the interaction of elements and the influence of the amount added, resulting in insufficient strength of the solder itself, which affects production and application.

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