What are several common causes that affect the production of tin beads?

The core component of electronic devices isPCBCircuit board, and with the gradual intelligence of electronic products,SMTSurface mount technology is facing new challenges. inSMTDuring processing, the quality of soldering is the key, and the selection of solder paste directly affects the quality of soldering. Now, by Shenzhen JJYSolder paste manufacturerLet's explain several main factors that affect the production of tin beads:

1The metal content of solder paste: The metal content in solder paste is generally88%~92%The mass ratio and volume ratio are approximately50%.The increase in metal content can enhance the viscosity of solder paste and the tightness of metal powder arrangement, thereby reducing the probability of solder bead formation.

2The degree of metal oxidation of solder paste: The higher the degree of metal oxidation, the greater the resistance to the bonding of metal powders during soldering, resulting in a decrease in solderability. Experiments show that the occurrence rate of solder beads is directly proportional to the oxidation degree of the metal powder. Therefore, the oxidation degree of the solder in the solder paste should be controlled at0.05%Below, the maximum limit is0.15%.

3The particle size of the metal powder in the solder paste: The smaller the particle size, the larger the overall surface area of the solder paste, which increases the oxidation degree of the finer powder and thereby intensifies the solder bead phenomenon. The experiment shows thatSMTIn surface mount technology (SMT) processing, solder paste with finer particle size is more likely to produce solder beads.

4The printing thickness of solder paste on the printed circuit board: The printing thickness is a key parameter for through-hole printing, usually in0.12mm~2.0mmBetween. Too thick solder paste may cause "collapse", thereby promoting the formation of solder beads.

5The amount and activity of flux: Excessive flux can cause local sagging of solder paste, increasing the possibility of solder bead formation. When the activity of flux is low, its deoxidation ability is weak, and it is also easy to form solder beads. The activity of no-clean solder paste is relatively low, so it is more likely to produce solder beads.

6In addition, the solder paste stored in the refrigerator before use should be brought back to room temperature after being taken out before use. Otherwise, the solder paste is prone to absorbing moisture, which may cause solder to splash and form solder beads during reflow soldering.

JJY Solder Paste Manufacturer mainly engages in lead-free solder paste.SMTSurface mount solder pasteLEDWe are engaged in the research and development, production and supply of solder pastes, lead-free solder wires, wave soldering rods and other solder solders. For more knowledge about electronic soldering, you can follow and contact us. Welcome to interact with us.