Solder pasteAs an indispensable part of the SMT production process, the particle size of the solder powder, the proportion of metal content, the content of flux, the stirring time, the reheating time, and the placement and storage time of the solder paste will affect the final printing quality of the solder paste.
At room temperature, the solder paste also has a certain viscosity so that the electronic components can be adhered to the desired location. Under the condition of a certain welding temperature, under the action of solvents and other auxiliary additives, a better connection effect can be achieved. Solder paste is usually made up of two parts, solder powder and flux, and each component has its own unique properties.
Fluxes mainly include activators, resins, thixotropic agents and solvents. The activator in the solder paste can effectively remove oxides from the solder parts and effectively reduce the surface tension of the tin alloy. The solvent allows for better agitation. Adjust the uniformity of the solder paste.
Solder powder is usually composed of tin-lead, tin-lead silver, tin-silver-copper, tin-bismuth silver, tin-bismuth alloy, etc., according to different ratios to achieve better welding results. According to the different requirements for the melting point, solder can also be divided into high-temperature solder, medium-temperature solder and low-temperature solder.
After understanding the function and composition of solder paste, it is necessary to store it better. Normally, solder paste needs to be controlled at 1-10 degrees Celsius. If unopened, it can be used for 6 months, and should not be placed in a place exposed to the sun.