|Self-fluxing brazing||Go To Index||Silver chromate test paper|
Lengthy storage periods will decrease the solderability of solder paste. For one, the high miscibility of solder powder and liquid fluxing agents is to blame. Due to the surface activation energy of the tiny solder particles, a chemical reaction takes place between the components already in the storage phase and a part of the activity of the solder surface is lost. On the other hand, the thixotropy of the flux plays a role as well. The shelf life (or storage life) of the solder paste must be guaranteed by appropriate procedures. Some also use the term pot life, but it is quite uncommon everywhere.