Talking about the classification characteristics of welding materials in SMT cooling conveyor processing


Release time:

2021-11-09

According to its component parts, the solder in SMT cooling conveyor processing can be divided into tin-lead solder, silver solder, and copper solder.

According to its component parts, the solder in SMT cooling conveyor processing can be divided into tin-lead solder, silver solder, and copper solder. According to the environmental humidity used, it can be divided into high-temperature solder (solder used under high temperature) and low-temperature solder (solder used under low temperature environment). In order to ensure the quality of soldering during patch processing, it is important to choose different solders depending on the object to be soldered. In the assembly of electronic products, tin-lead series solders, also called solders, are generally used.

SMT cooling conveyor

Solder has the following characteristics:
1. It has good electrical conductivity: Because tin and lead solder are good conductors, its resistance is very small.
2. Strong adhesion to component leads and other wires, not easy to fall off.
3. Low melting point: it can be melted at 180℃, and it can be welded with 25W external heating type or 20W internal heating type electric soldering iron.
4. It has certain mechanical strength: because the strength of tin-lead alloy is higher than that of pure tin and pure lead. In addition, due to the light weight of the electronic components, the strength requirements of the solder joints in the SMT cooling conveyor are not very high, so it can meet the strength requirements of the solder joints.
5. Good anti-corrosion performance: the welded printed circuit board can resist atmospheric corrosion without applying any protective layer, thereby reducing the process flow and reducing the cost.

Among tin-lead solders, those with a melting point below 450°C are called soft solders. Anti-oxidation solder is the solder used in automated production lines in industrial production, such as wave soldering. When this liquid solder is exposed to the atmosphere, the solder is extremely easy to oxidize, which will cause false soldering and affect the quality of soldering. Therefore, adding a small amount of active metal to the tin-lead solder can form a covering layer to protect the solder from further oxidation, thereby improving the soldering quality.