Brazing

The two metals to be joined are cleaned, heated and properly aligned for brazing, and flux (borax) is also applied on them. Proper clearance for filler material is maintained between the two pieces. Flux is added to protect joint surface from oxidation. The non-ferrous filler alloy (in liquid state) is introduced between the two metal pieces to be joined and allowed to solidify. On solidification, a strong joint is formed due to metallic bonding. The molten metal is allowed to flow by capillary action into the space.

The filler metal has a melting point of above 420°C, but it should be less than the parent metal. Brazing provides a much stronger joint as compared to the soft soldering process.

Dissimilar metals can also be joined by brazing.