DISTRIBUTION STATUS OF Fe IN FERRO SILICON NITRIDE

The distribution status of Fe in the ferro silicon nitride (FeSi_(3)N_(4)) material synthesized by flashing combustion process was analyzed by means of fluorometric measurement, XRD, SEM and EDS. The results show that when the grain size of FeSi75 used in preparing FeSi_(3)N_(4) is less than 0.074 mm, the Si_(3)N_(4) wrapped layer formed from the nitriding of Si on the surface of FeSi75 grain and ferrosilicon melts. With the continuous decrease of Si by nitrification, the Fe content increases accordingly. Thus the nitrification process becomes difficult to go on and Fe is remained and distributed inside the aggregation of silicon nitride mainly based on the two kinds of state, Fe_(3)Si and αFe. The thermodynamic analysis indicates that Fe_(3)Si and (α)Fe are the resultant of nitride reaction process.