| Silver-flo™ 453S is a cadmium free silver brazing filler metal. It combines a low brazing temperature with a short melting range. Silver-flo™ 453S contains 3% tin and a 0.2% addition of silicon, and as a consequence is free flowing. It produces smooth neat joints with small fillets. These characteristics have made it a popular choice for hand torch brazing of decorative brass components. This filler metal may be used to braze steel assemblies but is not recommended on carbon steel components that are subject to high impact or fatigue stress in service. It should be noted that this filler metal contains tin and may be described as being ‘hot-short’. It should not be quenched from high temperatures (in excess of 300°C) and care should be taken when it is used to braze components with widely differing coefficients of thermal expansion as in both cases cracking of the joints may occur. The optimum joint gap at brazing temperature is normally 0.05-0.15mm. Silver-flo™ 453S is used extensively for the brazing of brass components which require smooth neat joints. This filler metal can be used to join all the common engineering materials (excluding aluminum) – such as copper, copper alloys (including, brasses, bronzes, gun metal, nickel silvers, aluminum bronze, copper nickel) and stainless steel. It may be used for brazing tungsten carbide and PCD segments however where cracking of the carbide or wetting of the filler metal may be an issue specialized silver brazing filler metals containing nickel / manganese are often preferred. Information provided by Johnson Matthey Metal Joining |
