PCB supplier solder paste selection principle

There are many types and specifications of solder paste, even if it is the same manufacturer, there are differences in alloy components, particle size, viscosity, cleaning methods, etc., and the price difference is also great. How to choose the right welding incense has a great impact on product quality and cost. The pcb supplier should generally select solder paste in accordance with the specific production environment, with reference to the activity, viscosity, powder shape, particle size and melting point of the solder paste.

1. First determine the alloy composition. The alloy is the material that forms the solder joint, it forms an alloy layer with the interface of the metal to be welded, and the alloy composition also determines the welding temperature. Therefore, the pcb supplier should firstly determine the alloy composition and the alloy composition was selected mainly according to the electronic product and the process. We should choose the alloy composition that should be compatible with the soldered end of the component, and also consider the process factors such as soldering temperature.

2. Select the flux in the solder paste. The printability and solderability of the solder paste mainly depend on the flux. Therefore, after determining the alloy composition in the solder paste, the flux suitable for the production process should be selected.

3. Determine the ratio of alloy composition to flux in the solder paste. The ratio of the alloy composition to the flux directly affects the viscosity printability of the solder paste.

4.Pcb supplier selects the viscosity of the solder paste according to the process and assembly density of the solder paste applied.

At the same time, when selecting solder paste, you should select several companies' solder pastes for experimentation, and compare and evaluate printability, demold ability, thixotropy, viscous wettability, solder joint defects, residues, etc. Only by this way can we choose the right solder paste.