In the process of Pcb manufacturing circuit boards, solder paste and lead-free standards are used as green signs. Tin-lead solders have good mechanical and electrical properties. FASTPCBA pcb manufacturers have 6 solder paste models, including KOKI S3X58-M406. -3, Qianzhu lead-free solder paste L-038-0186 special printer, Sterner SnAg3.0Cu0.5 lead-free high temperature solder paste 305T800, Sterner SnAg1.0Cu0.5 lead-free high temperature solder paste 105t510, SnAg1. 0Cu0.5 Lead-free solder paste FB360 T4 special, special low flux residual solder paste (STN-Sn96.5Ag3.0Cu05 TYPE: 836).
In addition, the melting point of Sn63Pb37 eutectic solder is 183 ° C, which is just above the maximum working temperature of the electronic equipment, and the soldering temperature is range from 225 ° C ~ 230 ° C, which is still suitable for the high temperature that the component can withstand during the pcb soldering process , which is completely in line with the requirements of the welding technics. At the same time, tin-lead metals are very rich in the earth. The proven tin reserves are about 10 million tons, and the price of tin-lead metals is much lower than other metals. Therefore, tin-lead solder has been widely used for a long time because of its high performance and low price.
In tin-lead solder, bismuth and indium are added, the minimum melting point of the solder can be reduced to about 150 °C, and the tin content in the tin-lead solder is reduced to less than 10% or the metal such as silver is added thereto, and the melting point can be raised to above 300 °C. Solder Sn63Pb37 and Sn62Pb36Ag2 are the best choices from the viewpoint of melting point, mechanical properties and electrical properties. Sn43Pb43Bi14 is a better choice for low melting point solders.
The above is the professional information provided by the FASTPCBA manufacturer.