There are many methods of brazing, which are mainly distinguished according to the equipment used and the working principle. According to the heat source, there are infrared, electron beam, laser, plasma, glow discharge brazing, etc .; according to the working process, there are contact reaction brazing and diffusion brazing. Contact reaction brazing is a method of using solder to react with a substrate to generate a liquid phase to fill a joint. Diffusion brazing is to increase the thermal diffusion time so that the weld and the base material are sufficiently uniform, so as to obtain a joint with the same properties as the base material.

 

1. Soldering iron is used for welding small, simple or very thin parts.

 

2. Wave soldering is used for component welding of high-volume printed circuit boards and electronic components. At the time of welding, the molten solder at about 250 ° C forms a wave peak through the slit under the pressure of the pump, and the workpiece is welded by the wave. This method has high productivity and can realize automated production on the assembly line.

 

3. Flame brazing. Welding using a flame combusted by a combustible gas mixed with oxygen and oxygen or compressed air as a heat source. Flame brazing equipment is simple and easy to operate. Depending on the shape of the workpiece, multiple flames can be used for simultaneous heating and welding. This method is suitable for welding small and medium parts, such as bicycle frames and aluminum kettle nozzles.

 

4. Dip soldering: Part or all of the workpiece is immersed in a solder bath or salt bath containing only molten salt. The method has the advantages of uniform heating, rapid heating and accurate temperature control, and is suitable for large-scale production and welding of large parts. The salt in the salt bath is mainly composed of flux. After welding, a large amount of flux usually remains on the workpiece, which requires a lot of cleaning work.

 

5. Induction brazing A welding method that uses high frequency, intermediate frequency or power frequency induction current as a heat source. High-frequency heating is suitable for welding thin-walled pipe fittings. The use of coaxial cables and split induction coils can be brazed away from the power source, and is particularly suitable for welding certain large components, such as pipe joints on rockets that need to be disassembled.

 

6. Brazing in the furnace Put the workpiece and solder together in the furnace for heating and welding. Usually, a flux must be added. It can also be protected by reducing gas or inert gas, and heating is more uniform. Continuous production can be used for mass production.

 

7. Vacuum brazing heats the workpiece in a vacuum chamber. It is mainly used for welding high quality products and easily oxidizable materials.

Brass Brazing Alloy