The main reasons for printing solder paste when producing PCBA include the following 3 points:
1. Fixing electronic components: The solder paste has a certain viscosity, which can temporarily fix the SMT patch components on the pad position of the PCB or FPC window at room temperature to prevent them from falling off during transportation.
2. Reflow soldering: During the reflow soldering process, the solder paste melts at high temperature to form liquid tin, which infiltrates the solder ends of the components and the pads of the PCB or FPC window, and forms solid solder joints after cooling to ensure electrical and mechanical connections.
3. Improve production efficiency and reduce costs: The use of solder paste can save a lot of labor costs and improve production efficiency, especially on highly integrated PCB or FPC boards, such as mobile phone processing connectors, high-density resistors, etc.
What are the ingredients of solder paste used in the PCBA production process?
The solder paste used in the PCBA production process is mainly composed of tin powder, flux and other additives. Tin powder is composed of tin and other metal alloys, and flux helps wetting and removing oxides during welding. Solder paste can be divided into low-temperature, medium-temperature and high-temperature solder paste according to melting point and lead content, and there are lead and lead-free solder pastes respectively.
The role of solder paste used in the PCBA production process in the reflow soldering process: Preheating process: During the preheating process, the solder paste has small deformation during the collapse process, ensuring the stability during the soldering process.
Wetting performance: The solder paste has good wettability during reflow soldering, less solder splashing, and a small amount of solder balls are formed to ensure the quality of the solder joints.
Performance after cooling: The solder joints formed after soldering have sufficient strength to ensure that there will be no solder joint failure due to power-on, vibration and other factors.
Through the above explanation, it can be seen that the importance of solder paste in PCBA/FPCA production, it not only fixes electronic components, but also ensures the stability of electrical and mechanical connections through reflow soldering, while improving production efficiency and reducing costs.
