Reaction between Si3N4 and Fe-Ni alloy

In relation to the joining of silicon nitride ceramics to metal, the reaction between Si3N4 and Fe-Ni alloy was investigated under a nitrogen or an argon atmosphere at temperatures from 1123 to 1573 K. Reaction rates were determined by thermogravimetry and reaction products were examined by X-ray diffraction. Fe-Ni-Si solid solution, Ni3Si, Ni5Si2, NiSi2, Fe3Si, Fe5Si3 and FeSi were produced. The initial rate obeyed a linear rate law. The rate at the late stage of reaction was described by a parabolic rate law or Fick's second law. The reaction mechanism and the rate-determining step were proposed.