Tin bar is an important welding material for PCBA processing plants. Its good welding effect is welcomed by electronic processing factories. Tin bar is made of pure tin, and the price is relatively expensive. In order to obtain better welding effect, it is necessary to master some Soldering skills.
1. What is tin bar
Tin bar is a kind of solder bar made of pure tin. The bar shape is mainly used for the soldering of circuit boards. It has the advantages of easy tinning, bright solder joints, fullness and no false soldering. It is very suitable for wave soldering and immersion tin furnace. The global consumption of tin bars is large, and improper disposal of waste tin bars not only wastes tin resources, but may also cause harm to the environment and human body. Therefore, waste tin bars are generally recycled, which can also save costs.
2. Soldering skills when soldering tin bars
1. Working temperature
Tin bars are divided into lead tin bars and lead-free tin bars. The temperature of different tin bars is different when soldering. Sn63/Pb37 has lead and tin bars. Recommended soldering temperature: 255±10℃. Recommended soldering temperature for lead-free tin bars: 265±10℃.
2. Reduce the generation of tin bar scum
The dross is the oxide on the surface of the solder. When the temperature becomes high and the flow of the solder surface is too fast, the dross is more likely to be generated. At this time, the dross can be pushed to a corner, and some raw powder can be added to the dross. The dross can be converted into tin, and antioxidants can be added to the tin to reduce the oxidation of the tin.
3. To increase the tin bar in time
In the process of wave soldering, the tin content will decrease. When the decrease is to a certain extent, the oxidation of tin will be aggravated. At this time, tin bars should be added in time.
4. Removal of impurities Cu
When soldering with leaded tin bars, Cu reacts with Sn to form a layer of metal oxides. When this oxide is too much, it will affect the soldering quality, so impurities should be removed in time.
Tin bar is a good welding material for welding circuit boards, and the welding effect is good. However, in the process of welding, if you do not master good welding skills and are careless, you will not be able to exert the good performance of the tin bar, which will ultimately affect the welding quality.