Characteristics of brazing

 First, the surface of the joint is smooth, airtight, stable in shape and size, and the structure and performance of the weldment does not change much, and the same or different metals and some non-metals can be connected. When brazing, heating the workpiece as a whole can also be used to weld many welds at one time, which improves productivity. However, the strength of brazed joints is low, and lap joints are often used to increase the strength of the joint by increasing the length of the lap; in addition, the preparation work before brazing requires higher. The second is that the solder melts but the weldment does not melt. In order to make the brazing part firmly connected and enhance the adhesion of the brazing material, flux should be used during brazing to remove the oxides on the surface of the brazing material and the weldment. The brazing filler metal has high strength and can be used to connect load-bearing parts. It is widely used, such as cemented carbide cutting tools and bicycle frames. Soft solder has low welding strength and is mainly used for welding parts that do not bear load but require good sealing properties, such as containers and instrument components. Brazing uses an alloy with a lower melting point than the base material as the brazing filler metal. The brazing filler metal melts when heated, and fills and remains in the joint gap by wetting and capillary action. The base material is in a solid state and relies on the liquid brazing filler metal and solid base material. The interdiffusion between materials forms a brazed joint.