Reflow soldering, foreign name 回流焊, reflow soldering technology is no stranger in the field of electronic manufacturing. The components on various hardware boards used in our computer are welded to the circuit board by reflow soldering.
Reflow soldering is to weld the components to the PCB board and mount the components on the surface. The reason why it is called "reflow welding" is that the gas circulates in the welding furnace to produce high temperature, so as to achieve the purpose of welding.
There is a heating circuit inside the reflow soldering furnace, which heats the air or nitrogen to a certain temperature and then blows it to the circuit board which has been attached with components. Depending on the effect of hot air flow on the solder joint, the colloidal flux carries out physical reaction under a certain high temperature air flow to achieve SMD welding; The welding material on both sides of the component melts and connects with the motherboard.
The advantage of this welding technology is that the temperature is easy to control, the excessive oxidation can be avoided in the welding process, the variable is small, and the manufacturing cost is easier to control;
The quality of reflow soldering will be affected by many factors, the most important factor is the temperature curve of reflow soldering furnace and the composition of solder paste in the process of electronic processing.
Now the high performance reflow soldering furnace which is often used can adjust and control the temperature curve more conveniently; Therefore, in the trend of miniaturization and high density, solder paste printing has become the key factor of reflow soldering quality, template, printing and solder paste can affect the quality of solder paste printing.