What precautions should be taken for lead-free solder paste at different temperatures?

Lead-free solder pasteWhat should be noted at different temperatures? For friends who have used lead-free solder, it is known that lead-free solder paste has different temperatures, with distinctions between low and high temperatures. The required temperatures for different products, components, substrates, etc. are also different. Lead-free high-temperature solder paste, as the name suggests, is used in high-temperature environments. The same principle applies to low-temperature environments. Therefore, when choosing solder paste, one should not be too blind. It is necessary to select the melting point of the solder paste based on one's own actual situation. The following are a few points introduced by the editor of Youjia Jinyuan:

1High-temperature solder paste has excellent preservation stability.

2It has good printability (fluidity, release property, continuous printability).

3After printing, it should be corrected within a certain period of timeSMD It has a certain adhesive property.

4After welding, a good bonding state should be achieved, and the weld points should be smooth and clean.

5The composition of its flux should have high insulation and low corrosiveness.

6It has good cleaning properties for flux residues after welding, and no residue components should be left after cleaning.

High temperature and low temperatureLead-free solder pasteThe main difference lies in the melting points. High-temperature lead-free solder paste is generally composed of metals such as tin, silver, copper and aluminum, while low-temperature solder paste is usually made up of alloys such as tin, bismuth and lanthanum series. The melting point of low-temperature solder paste is generally138℃High temperatures are generally217-227So if you want to distinguish different furnace temperatures, you might as well pass all these types of solder pastes through the furnace and set the reflow soldering temperature curve as the low-temperature solder paste. If there is one type that drops components severely or does not stick after passing through the furnace, it is the high-temperature lead-free solder paste, because the melting point of high-temperature lead-free solder paste is217The maximum temperature of low-temperature solder paste may be220It just reaches the melting point of high temperature, so if the tin cannot be melted, it will cause the component to drop. Lead-free high-temperature solder paste is affected by humidity and temperature. Therefore, it is recommended that the working environment be at a room temperature of 23 to 25 degrees Celsius and a humidity of 60% is ideal. The viscosity of the solder paste can be adjusted to an appropriate level within the range of 23 to 25 degrees Celsius. If the temperature is too high, it will cause the viscosity to be too low, and if it is too low, it will cause the viscosity to be too high, resulting in an imperfect printing effect. Due to the hygroscopicity of solder paste, in a high-temperature and humid environment, the solder paste will absorb moisture from the air, resulting in solder balls and spatter.

The solder paste of Shenzhen JJY brand has gone through many years12A solder paste and wire manufacturer specializing in the annual research and development of solder paste, solder wire, solder wire, lead-free solder paste, leaded solder paste, solder rods, leaded solder paste, etc. Choose the solder paste manufacturer of JJY brand for solder paste.