Forms Of Brazing Alloys

Brazing alloy or the filler metal is the metal that is used to join two different metals through the brazing process. Filler metal is the metal that goes into the space between the two metals to be joined, melts in there and then flows down the joining surface before it goes through brazing. This makes it a strong joint between two dissimilar metals. It is very much like welding and soldering, but different than these processes in a lot of aspects. All three processes have different advantages, disadvantages and therefore different applications.


Coming back to brazing alloys or the filer metals, the choice of brazing alloys differs from metal to metal. Base metal characteristics need to be matched with the filler metal metals properties to ensure that they are chemically compatible. This is important for two reasons. One, safety in brazing. Two, achieving desired results from the process. The commonly used brazing alloys are aluminium, nickel, steel,titanium,copper, brass, etc.


Just like the careful choice of the properties, choosing the suitable form of the brazing alloys is also of key importance. Brazing alloys are available in quite a few forms that are useful in different metal brazing. To ease out brazing of different types of metals, different forms of brazing alloys, namely – paste, powder, rods, sheets & wires. Other shapes available are rings and discs.


Choosing the filler metal as well as the suitable form is dependent on the base metals being used for the brazing application and the shape of edges to be joined. Different shapes are used to fit them well in place in between the gap. For, example the wire, strip and rod forms are for face feeding, where as the brazing alloy paste is used because of its ease of applying in complex shapes of joints. Similarly using a powder form of alloy also does away with any limitations with respect to the shape of the joint.