Electronic solder is a general term for metal alloy materials used for welding, surfacing and brazing joints. It includes wire (wire), electrode (electrode) and solder (brazing and brazing alloys). The melting temperature of the solder is usually not lower than the solid phase of the base metal. Its chemical composition, mechanical properties and thermal properties are similar to those of the base metal, such as various electrodes and flux cored wires. The weld strength is usually not lower than the base metal itself, and the melting temperature of the solder must be lower than the solid line of the base metal. The chemical composition of the brazing filler metal is often far away from the base metal. The brazing seam is small and precise in size. However, the strength of the brazing seam is mostly inferior to that of the base metal itself, and its corrosion resistance is poor. Solders, such as arc welding, often exceed the base material and solder itself, and there are no soft or hard parts. Brazing joints of copper, zinc (copper-zinc alloy), silver solder (silver-copper alloy) and other solders are firm, mainly used for high strength joints, solder (tin-lead) and other solders.
The main alloy welded joints have low strength. They are mainly used to connect small joints without excessive strength, such as electronic instruments, instruments, electrical appliances and wires. The main function of solder is to connect welds and form circuit channels. Conditions for electronic solders:
1) The melting point of solder is lower than that of welder.
2) Easy to combine with the weld, it must have a certain compression capacity.
3) Must have good conductivity.
4) It is necessary to have a faster crystallization rate.