With the development of high-temperature technologies such as steel smelting, the development and research of refractory materials and raw materials is urgent. Synthetic raw materials are increasingly used as a promising refractory material. Ferrous silicon nitride (Fe-Si3N4) is a new synthetic raw material that has appeared in recent years. It is prepared from FeSi75 iron alloy using nitriding technology and high-temperature synthesis process.
Characteristics of ferrosilicon nitride
Ferrosilicon nitride for refractory materials is a gray-white (or brown) powder, and ferrosilicon nitride for steel-making is gray-white granular material. Silicon nitride is a mixture of silicon nitride and iron, generally containing 75% to 80% (w) Si3N4, 12% to 17% (w) Fe, and free Si is not more than 1% (w). Si3N4 in ferrosilicon nitride has two crystal forms, α and β, both of which are hexagonal crystals. The iron element exists in the form of α-Fe or (and) iron silicide.
Because ferrosilicon contains Si3N4 phase, it has some excellent properties of Si3N4, such as high refractoriness, good corrosion resistance, high mechanical strength, good thermal shock resistance, low thermal expansion rate, and high oxidation resistance. It has a series of advantages such as good properties; it also has good sintering properties because it contains Fe plastic phase. At the same time, compared with silicon nitride, ferrosilicon nitride is cheaper and easier to promote and produce industrially. Therefore, it has been used as a raw material for refractory materials, high-temperature binding phases and high-temperature structural materials. It is now widely used in blast furnaces. Iron ditch castable. In recent years, there has been increasing research on ferrosilicon nitride materials and their applications in refractory materials.
