What types of Pcb factory solder paste? In the Pcb manufacturing process, solder paste is often used, but there are different types of solder paste, which is the need to use solder paste according to the products produced.
First, lead solder paste and lead-free solder paste
Lead-containing solder paste contains lead, which is harmful to the environment and human body, but has good welding effect and low cost, and can be applied to some electronic products that are not required for environmental protection. The lead-free solder paste contains only a trace amount of lead, which is harmful to the human body. It is an environmentally friendly product and is used in environmentally friendly electronic products. Foreign customers will require the use of lead-free solder paste.
Second, high temperature solder paste, medium temperature solder paste, low temperature solder paste
1. High-temperature solder paste refers to the lead-free solder paste that is usually used. The melting point is generally above 217 °C, and the welding effect is good.
2, medium temperature solder paste, commonly used lead-free medium temperature solder paste melting point around 170 ° C, medium temperature solder paste is mainly used imported special rosin, good adhesion, can effectively prevent slump.
3. The melting point of the low-temperature solder paste is 138 ° C. The low-temperature solder paste mainly adds the antimony component. When the components of the patch cannot withstand the temperature of 200 ° C and above and the reflow process is required, the solder paste is used for the soldering process. Protected from high temperature reflow soldering originals and PCBs, it is very popular in the LED industry.
Third, tin powder particle size
According to the particle diameter of the tin powder, the solder paste can be divided into 1, 2, 3, 4, 5, and 6 grade solder pastes, of which 3, 4, and 5 powders are more commonly used.
The more precise the product, the tin powder needs to be smaller, but the smaller the tin powder, the corresponding increase in the oxidation area of the tin powder. In addition, the shape of the tin powder is round to help improve the quality of printing.
The more difficult the products manufactured by Pcb, the more important the choice of solder paste. The solder paste suitable for the product can effectively reduce the quality defects of solder paste printing, improve the quality of reflow soldering, and reduce the cost of production.