Soldering and brazing are methods of joining metals together. Brazing joins two metals together by heating and melting a filler; the filler has a melting temperature that must be below that of the metal pieces. Flux is often used in brazing.
Brazing can be used to join different metals such as silver, gold, copper, aluminum, and nickel. Soldering has a lower temperature compared to brazing. Solder can be used for different metals such as gold, silver, copper, brass, and iron. A brazing bond is stronger than a solder bond.
Solder was once made mainly of lead. Solder those not necessarily require a fluxing agent. Soldering is used in the electronic industry to form a permanent connection between electronic components. In brazing, flux is used to promote wetting and remove oxides from base material so that the filler metal bonds well with metal parts.