The difference between spot tin and immersion tin for wire rod.

The difference between soldering tin on wires and dipping tin.

1. Soldering process is a process of immersing the copper surface of PCB in molten solder, and then removing the solder surface with hot air. There are two ways: lead-free spot tin and lead-free spot tin. At present, most of the tin-spot spraying processes are non-spot spraying, which has been gradually eliminated by the market because of its harm to human health and the environment. The process of tin spot is relatively simple, so the cost is high.

2. Tin dipping process is a surface treatment process of depositing a tin coating on the copper surface of PCB by chemical method, which mainly plays an anti-oxidation role. It should be noted that the tin dipping process uses lead-free tin solution, and the tin spraying process uses tin alloys or other metal alloys containing tin and lead. Because the intermetallic compound of copper or tin is easy to appear in the process of tin dipping, and the intermetallic compound of copper or tin is easy to solder in high temperature environment, the service life and storage market of PCB treated by tin dipping process are shorter than that of tin spraying process.