Damp-proof rustproof coating solder ring and preparation method thereof

Abstract

The invention relates to the field of welding materials, in particular to a damp-proof rustproof coating solder ring and a preparation method of the damp-proof rustproof coating solder ring. The damp-proof rustproof coating solder ring comprises a solder inner core, a metal coating, a high-activity soldering flux layer, a weak dampness absorption soldering flux layer and an outer damp-proof layer,wherein the periphery of the solder inner core is plated with the metal coating, the periphery of the metal coating is coated with the high-activity soldering flux layer, the periphery of the high-activity soldering flux layer is coated with the weak dampness absorption soldering flux layer, and the outer damp-proof layer adheres to the periphery of the weak dampness absorption soldering flux layer; and the solder inner core is spring-shaped solder, the metal coating is a tin coating or an indium coating, the high-activity soldering flux layer is made of QJ102 silver soldering powder, the weak dampness absorption soldering flux layer is made of FB308S silver soldering powder, and the outer damp-proof layer is made of an organic binding agent material. The solder ring can prevent the solder inner core from being corroded, and the soldering flux activity is high.

Description

technical field [0001] The invention relates to the field of welding materials, in particular to a moisture-proof and rust-proof coating solder ring and a preparation method thereof. Background technique [0002] At present, only cored solder rings and coated solder rings are used in pipeline brazing. Since the processing performance of cored solder is restricted by its composition, there is a problem of poor deep processing performance. The disadvantage is that it can only be prepared into strips, and it is difficult to prepare into rings. Therefore, the most promising application prospect for brazing of pipelines in industries such as air conditioners and refrigerators is the sheathed solder ring. [0003] There are three disadvantages in the currently disclosed sheathed solder ring: 1. The structural form is to prepare a solder paste by mixing an organic adhesive and flux, and then coat the flux on the outer periphery of the solder inner core, (Chinese patent CN202804495...

AI Technical Summary

Problems solved by technology

[0002] At present, only cored solder rings and coated solder rings are used in pipeline brazing. Since the processing performance of cored solder is restricted by its composition, there is a problem of poor deep processing performance. Defect, it can only be prepared into strips, and it is difficult to prepare into rings. Therefore, the most promising application prospect of pipeline brazing in air conditioners, refrigerators and other industries is the coating solder ring.

[0003] There are three disadvantages in the currently disclosed sheathed solder ring: 1. The structural form is to prepare a solder paste by mixing an organic adhesive and flux, and then coat the flux on the outer periphery of the solder inner core, (Chinese patent CN202804495 U discloses " a kind of brazing filler metal that is coated with coating ", and it is that coating coating is applied on the solder rod; The coating is to mix the organic adhesive and flux first, and then press-coat the flux with the adhesive on the surface of the brass brass), although the excess organic binder in this coating plays a role Moisture absorption, but during the brazing process, the adhesive is thermally decomposed and carbonized, producing a large amount of harmful gas, which not only pollutes the environment, but also damages the health of the operator, which is not environmentally friendly; at the same time, carbon residues in the brazing seam produce inclusions, Reduced brazing reliability

2. The coating thickness of the above-mentioned structural form is too large, and the heat transfer between the welded pipeline and the coating solder ring is slow during induction heating (heating the welded pipeline during high-frequency induction brazing, and the heat transfer from the welded pipeline to the coating The brazing filler metal ring, which reaches the melting point of the brazing filler metal, melts and wets, and fills the seam to the gap of the welded pipeline), which affects the brazing efficiency; 3. The coating of the brazing filler metal ring often contains boric anhydride, potassium fluoride and other inorganic substances , it is easy to absorb moisture and fall off blocks, and the flux layer after moisture absorption is corrosive, which seriously corrodes the inner core of the solder covered by the flux layer, especially the copper-phosphorus solder is easy to oxidize and corrode and " "Rust", the "rust" of the solder inner core will seriously affect the appearance and performance of the solder ring. In order to prevent the solder core from corroding the solder core after the flux layer absorbs moisture, it is necessary to choose a flux with weak moisture absorption. The activity of the flux is very low (the main function of the flux is to remove the oxide film on the surface of the welded metal and protect the welded metal from oxidation. The activity of the flux mainly refers to the ability to remove the oxide film)

Images