How to avoid defects during SMT patch soldering?

inSMTIn the surface mount technology (SMT) processing in factories, soldering is undoubtedly a very important processing step. If it is not done well during the soldering process, it will affect the entire processpcbIn the production of boards, even the slightest deviation can lead to substandard products. In severe cases, the products may even be scrapped. To avoid mistakes due to poor weldingsmtThe processing quality has an impact, and the welding process should be given due attention. SoSMTHow to avoid defects during surface mount technology (SMT) soldering? The following is JJYSolder paste manufacturerLet me give you a brief introduction:

1. Weld the heating bridge. In surface mount technology (SMT) processing, the welding thermal bridge serves to prevent solder from forming a bridge. If an error occurs during this process, it will lead to uneven distribution of solder. The correct soldering method is to place the tip of the soldering iron in the middle of the pins of the pad, with the solder wire close to the tip of the soldering iron. When the solder paste melts, move the solder wire between the pad and the pins, and place the soldering iron above the solder wire. Only in this way can a good solder joint be produced and the impact on processing be reduced.

Ii. Force applied when soldering the pins. During the processing, if too much force is applied when soldering the pins, it can easily lead to problems such as the pad of the surface mount lifting, delamination or depression. So during the welding process, in order to ensuresmtThe quality of surface mount technology (SMT) processing does not require excessive force. Just make the tip of the soldering iron touch the solder pad.

Iii. Selection of Soldering Iron Tips. During the welding process,The selection of the size of the soldering iron tip is also very crucial. If the size is too small, it will increase the retention time of the soldering iron tip, leading to the appearance of cold soldering points. If the size is too large, it will cause the heating to be too fast and burn the patch. Therefore, we need to select the appropriate size of the soldering iron tip based on its length and shape, as well as its heat capacity and contact surface.

Iv. Temperature Setting. Temperature is also a very important step in the welding process. Setting the temperature too high can cause the solder pad to lift up, and excessive heating of the solder can damage the surface mount. Therefore, it is necessary to pay attention to the setting of the temperature. Setting a suitable temperature is also particularly important for the processing quality.

V. Use of Flux. During the implementation of the relevant process, if too much flux is used, it may cause problems such as the stability of the lower solder joint. In severe cases, corrosion or electron transfer may also occur.

Vi. Transfer welding operations. Transfer soldering refers to placing the solder on the tip of the soldering iron first and then transferring it to the connection point. Improper operation may result in poor wetting. Therefore, we should first place the soldering iron tip between the pad and the pin. When the solder wire approaches the soldering iron tip and waits for the solder to melt, move the solder wire to the opposite side, and then place the solder wire between the pad and the pin. Place the soldering iron on the tin wire. When the tin melts, move the tin wire to the opposite side.

Vii. Finishing or rework. The taboo in the process is to make modifications or rework in pursuit of perfection. However, this approach is not only unacceptable but also, in pursuit of perfect product quality, involves repeated modifications or rework, which can easily lead to damage to the circuit board/pcbThe metal layer of the circuit board is fractured.

Shenzhen JJY Industrial Technology Co., Ltd. mainly engages in the production and operation of:SMTSolder paste manufacturers of solder paste, syringe solder paste, lead-free solder wire, wave soldering bar, automatic soldering wire, etc.