Viscosity and surface tension are important properties of PCB A solder, and good PCBA solder should have low viscosity and surface tension when melted. Whether it is reflow, wave or hand soldering, surface tension is a detriment to forming good solder joints. Next, Shenzhen PCBA manufacturer - Shenzhen Lingzhuo Electronics will introduce how to reduce the surface tension and viscosity in PCBA welding process.
The role of surface tension in PCBA soldering processing
Surface tension is opposite to the direction of wetting force, so surface tension is one of the factors that are not conducive to wetting.
Whether it is reflow, wave or hand soldering, surface tension is a detriment to forming good solder joints. But surface tension can be used again in SMT chip processing relow soldering.
When the solder paste reaches the melting temperature, under the action of balanced surface tension, a self-positioning effect will occur, that is, when the component placement position deviates a little, under the action of surface tension, the component can be automatically pulled back Approximate target location.
Therefore, the surface tension makes the reflow process looser on the placement accuracy requirements, and it is easier to achieve a high degree of automation and high speed.
At the same time, because of the characteristics of "reflow" and "self-positioning effect", the SMT reflow soldering process has stricter requirements in terms of pad design and component standardization.
If the surface tension is unbalanced, even if the placement position is very accurate, PCBA welding defects such as component position deviation, tombstones, and bridges will occur after PCBA welding processing.
During wave soldering, due to the size and height of the component body itself, or because the high component blocks the short component, the oncoming tin wave is blocked, and the shadow effect is caused by the influence of the surface tension of the tin wave, and the liquid is formed on the back of the component body. The blocking area that the PCBA solder cannot infiltrate, resulting in leakage soldering.
The above is the introduction of how to reduce the surface tension and viscosity in PCBA welding process. I hope it can help everyone. At the same time, if you want to know more about PCBA processing information, you can mail to lisa.xu@pcb-hero.com
The role of surface tension in PCBA soldering processing
Surface tension is opposite to the direction of wetting force, so surface tension is one of the factors that are not conducive to wetting.
Whether it is reflow, wave or hand soldering, surface tension is a detriment to forming good solder joints. But surface tension can be used again in SMT chip processing relow soldering.
When the solder paste reaches the melting temperature, under the action of balanced surface tension, a self-positioning effect will occur, that is, when the component placement position deviates a little, under the action of surface tension, the component can be automatically pulled back Approximate target location.
Therefore, the surface tension makes the reflow process looser on the placement accuracy requirements, and it is easier to achieve a high degree of automation and high speed.
At the same time, because of the characteristics of "reflow" and "self-positioning effect", the SMT reflow soldering process has stricter requirements in terms of pad design and component standardization.
If the surface tension is unbalanced, even if the placement position is very accurate, PCBA welding defects such as component position deviation, tombstones, and bridges will occur after PCBA welding processing.
During wave soldering, due to the size and height of the component body itself, or because the high component blocks the short component, the oncoming tin wave is blocked, and the shadow effect is caused by the influence of the surface tension of the tin wave, and the liquid is formed on the back of the component body. The blocking area that the PCBA solder cannot infiltrate, resulting in leakage soldering.
The above is the introduction of how to reduce the surface tension and viscosity in PCBA welding process. I hope it can help everyone. At the same time, if you want to know more about PCBA processing information, you can mail to lisa.xu@pcb-hero.com