Brazing is a process of joining two pieces of metal, in which both filler material and the parent metal are heated up, and the filler material melt into a liquid state between the pieces of parent metal. The melting temperature of the filler material is lower than the melting temperature of the parent metal.

The advantages brazing are minor distortion, smooth appearance and dissimilar metals and parts can be joined easily. Brazing is used for the fastening of pipe fittings, tanks, credible tips on tools, radiators, heat exchangers, electrical past and the repair of castings.

According to the melting point of filler material, brazing could be defined as hard brazing (>450°C) and soft brazing (<450°C). Whereas the brazing above 900°C is called high temperature brazing.

Different to fusion welding, brazing does not melt the base metals; Different to pressure welding, brazing does not press the working piece.

There are many forms of brazing material, such as powder, paste, belt, foil, rod, wire etc.