Simulation of Solidification Process of Pure Fe Brazing

In order to study the influence of Fe element on microstructures of brazing joint of stainless steel and nickel-based filler metal,vacuum brazing for pure Fe with BNi-2+40%BNi-5 composite filler was performed,the microstructure,element composition distribution,phase composition and element diffusion of the brazed joint were investigated by metallographic analysis,scanning electron microscopy(SEM),energy dispersive spectrometry(EDS) and Thermo-Calc and Dictra softwares.The result indicates that the brazed seam of pure Fe are composed of γ-Ni solid solution and Cr-B intermetallic compound.According to the calculations of Thermo-Calc and Dictra softwares,the solder solidification will not end when cooling down the temperture to 1 173 K,during which eutectic reaction has happened.The calculations of phase composition and element diffusion behaviors coincide with the experimental results,which can provide a guidance for new brazing technologies in a certain degree.