Brazing Properties of Novel Fe-based Amorphous Brazing Foils for Joining Steel

Alloy systems in the field of brazing must meet ever-increasing requirements in terms of mechanical properties. Cost efficiency and environmental compatibility must always be considered. To limit time-consuming alloy design, the use of thermodynamic simulation is becoming increasingly important in scientific research. Using a thermodynamic database, the authors recently developed two novel Fe-based brazing foils. These foils are used for brazing X6CrNiMoTi17-12-2 in a vacuum furnace at T = 1,200 °C for t = 10 min. Investigations of the joints are performed using ultrasonic c scan, SEM (scanning electron microscopy) / EDS (energy dispersive spectroscopy) and shear testing. For comparison, all investigations are carried out in parallel with an industrial Fe-containing foil. The novel Fe-based brazing foils can be used to produce material-bonded joints with excellent wetting on the X6CrNiMoTi17-12-2. SEM images show that strong B diffusion has taken place towards the grain boundaries in the diffusion affected zone of the X6CrNiMoTi17-12-2. The shear strength is good and exceeds τ > 200 MPa for both Fe-based brazing foils. Investigations have shown that efficient alloy design is possible with the aid of thermodynamic simulation. This saves time-consuming trial-and-error testing and can be expanded in the future by adding further elements.