Reflow soldering, is a soldering technology developed with the advent of miniaturized electronic products, and is mainly used for soldering of various surface-mount components. The solder of this soldering technique is solder paste. Apply appropriate amount and appropriate form of solder paste on the pad of the board before placing the SMT component in the corresponding position; the solder paste has a certain viscosity to fix the component; then let the board that placed with components enters the reflow soldering device. The transfer system drives the board through various temperature zones in the device. The solder paste is dried, preheated, melted, wetted, and cooled to solder the components to the printed board. The core part of reflow soldering is to use an external heat source to heat the solder to melt and infiltrate again, completing the soldering process of the board.
The reflow soldering operation method is simple, high in efficiency, good in quality, good in consistency, and saves solder (only a thin layer of solder under the leads of the components), which is an electronic product assembly technology suitable for automated production. The reflow process has now become the mainstream of SMT board assembly technology.