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Soft Solder Information

Soft soldering is a process created by the molten metals contact with the metal sufaces. The solder dissolves and joins with the parent metals. Tin has a big affinity to dissolve and join with other metals such as copper, brass, silver etc. The soft solder alloy will difuse into the metal surfaces and join with these to form a new surface alloy. It is this effect taht gives the soldering its strength. Tin increasingly dissolves other metals - the higher the temperature.

Too much copper dissolved in the melting bath at relatively low temperatures, can cause soldering problems, especially in electronics. A bath with excess copper can give inhomogeneous and brittle joints. Do not start with copper containing solders, this can create less space in the melting bath due to the copper solution. Prevent having copper containing components in the bath for longer periods of time. In wave soldering, where there can be two waves: the first wave removes the flux and the second wave can contain a thin layer of soldering-oil.

Metalli´s product range has two main groups of soft solder products:

  • Tin-lead soft solder - this type of soft solder is standard for soft soldering at especially low temperatures. (See soft solder for electronics).
  • Silver containing soft solder - ie. soft solder which contains silver + one or more of the following metals: Tin, Lead, Copper, Zink or Cadmium. (See soft solder for industry).

Chemical symbol:

Sn = Tin

Pb = Lead

Sb = Antimony

Cu = Copper

Ag = Silver