What are brazing fillets and how can they help my braze joints?
A fillet is nothing more than solidification of molten braze alloy filler metal on the external part of a braze joint. They are an expected outcome of the brazing process. Fillets do not add to the strength of brazed assemblies. However, a brazing fillet can tell a lot about the brazed joint itself. First and foremost, brazing fillets should be small and concave. If your brazing fillet is raised and otherwise large, it is likely an indication of one or more of the following factors: the brazing alloy filler metal lacks good compatibility with the base metals, braze joint contamination, inhibited flow of braze alloy filler metal due to incorrect temperature or clearance. A brazing fillet should simply indicate that your brazing alloy has flowed adequately around your properly designed assembly.Back