Soldering technology is a way to closely combine two metals with low thermal resistance with solder paste, which is commonly aluminum & aluminum, copper & aluminum and copper & copper.

This soldering process is widely used with CPU cooler and heatsink.

Completely remove the oil stain, dirt and insulating layer on the base metal before soldering; When soldering, heat the base metal first, heat the thick part first, and then heat the thin part; Heat copper parts first, and then aluminum parts; Move the soldering gun back and forth to heat the soldering part evenly. When the temperature of the weldment reaches 450-500 ° C, add the soldering wire to the soldering part to melt the soldering wire evenly into the weld ( the flame can not be directly aligned with the soldering wire for heating, and the soldering wire is mainly melted by the temperature of the base metal ). Then slightly sweep the soldering part with flame to ensure the spreading and positioning of solder at the soldering part, remove the soldering gun and let it cool naturally, and then the soldering can be completed.

Pure copper also known as red copper, its specific gravity is 8.93 g / cm3, melting point is 1083 ℃, with high electrical conductivity, thermal conductivity, plasticity, corrosion resistance and good low temperature performance. It is one of the important metal materials in industry.

(1) Strong thermal conductivity, copper has high thermal conductivity, which requires high-power heat source; The soldering cpu cooler heat sink shall be preheated before soldering.

(2) High fluidity, molten copper has good fluidity, and can only be welded at the flat soldering position. If one side butt soldering is to be carried out at a spatial position, a backing plate must be added to ensure penetration and good forming.

Aluminum is second only to silver, copper and gold in conductivity. Although its conductivity is only two-thirds of that of copper, its density is only one-third of that of copper. Therefore, the quality of aluminum wire is only half that of copper wire when transporting the same amount of electricity.

The oxide film on the surface of aluminum not only has corrosion resistance, but also has certain insulation performance, so aluminum is widely used in electrical manufacturing industry, wire and cable industry, and wire and cable.

Aluminum is a good conductor of heat. Its thermal conductivity is three times greater than that of iron. In heat sink industry, aluminum can be used to make all kinds of heat exchangers and heat dissipation materials.