Environment-friendly coated copper brazing filler metal

Abstract

The invention discloses environment-friendly coated copper brazing filler metal. The environment-friendly coated copper brazing filler metal comprises a copper brazing filler metal inner core and a copper brazing flux coating adhering to the outer side of the copper brazing filler metal inner core. The copper brazing flux coating comprises at least one of inorganic fluoride, potassium fluotitanate, anhydride, boric acid, borate, fluoroaluminate and elemental boron; the raw materials of copper brazing fluxes, polyvinyl alcohol, methylcellulose and water are prepared into a brazing flux solution according to a certain proportion, the surface of the copper brazing filler metal inner core is directly coated with the brazing flux solution, and the coated copper brazing filler metal can be obtained after the brazing flux solution is dried. The environment-friendly coated copper brazing filler metal has the advantages that the production process is simple, the production cost is low, the finished brazing filler metal is environmentally friendly, free of pollution and convenient to use, and the coating bonding strength is high; the brazing fluxes can be pre-added conveniently, quickly, quantitatively and efficiently, and the use amount of the brazing fluxes is effectively reduced; since the coated copper brazing filler metal does not contain organic bonding agents, the coated copper brazing filler metal meets the ROHS standard, pollution to environment during brazing and burning is greatly reduced, body health of operators is protected, and the labor intensity of the operators in the brazing process is greatly relieved.

Description

technical field [0001] The invention relates to a copper solder with a coating, in particular to an environment-friendly coated copper solder. Background technique [0002] The traditional brazing process is manual flame brazing of wire or strip copper brazing material. Flame brazing temperature is high and heating is fast, but it is prone to problems such as uneven heating and overburning, and brazing copper and other fast heat conduction Metals take longer to heat up. When brazing, wire or strip-shaped copper brazing filler metal is used or pre-coated on the workpiece before heating. The amount of brazing filler metal can not be guaranteed, and problems such as solder leakage and solder blockage are prone to occur, and subsequent rework , rework or even scrapping will cause waste of copper solder and raw materials, increasing manufacturing costs. In addition, the process of soldering flux or pre-fluxing adds a pre-soldering operation, increases the process and operation ...

AI Technical Summary

Problems solved by technology

[0002] The traditional brazing process is manual flame brazing of wire or strip copper brazing material. Flame brazing temperature is high and heating is fast, but it is prone to problems such as uneven heating and overburning, and brazing copper and other fast heat conduction Metal takes longer to heat up

When brazing, wire or strip-shaped copper brazing filler metal is used or pre-coated on the workpiece before heating. The amount of brazing filler metal can not be guaranteed, and problems such as solder leakage and solder blockage are prone to occur, and subsequent rework , rework or even scrapping will cause waste of copper solder and raw materials, increasing manufacturing costs

In addition, the process of soldering flux or pre-fluxing adds a pre-soldering operation, increases the process and operation time, and adds a variable to the brazing process, which affects the consistency of the weld and the stability of the quality

This kind of brazing process is complicated, the production efficiency is low, and it is difficult to accurately control the amount of flux used. Too much or uneven flux often occurs, resulting in waste of flux, and the residue of flux is difficult to clean, and it is easy to corrode the joint.

[0003] In view of the problems referred to above, there are also some relevant reports in China, such as the Chinese patent CN202804495 U which discloses "a kind of brazing filler metal coated with a coating", which is to press-coat the coating on the brazing filler metal rod, but this method can only produce The brazing material rod with thicker coating cannot be used to produce non-strip or rod-shaped coating solder; Chinese patent CN101190479 A also discloses a kind of "red copper tungsten argon arc welding welding wire with flux coating layer", which is The acrylic resin adhesive is used to bond the flux, and then the flux is pressure-coated on the welding wire; the signed article "Development of Coated Brass Solder" also introduces a layer of coating on the surface of filamentous brass solder, coating The solder is bonded together by an organic adhesive

Since the above methods all use organic adhesives to press-coat the flux onto the welding wire, the burning during welding not only pollutes the environment, but also damages the health of the operator, which is not environmentally friendly.