THE ANALYSIS OF STRUCTURE-CHEMICAL STATE OF DUPLEX SYSTEM OF SILICATES-SILICIDES OF ALKALINE EARTH METALS

The classification and structuring of oxide and metallic phases of binary duplex systems of silicates-silicides of alkaline earth metals are carried out in the work. This will determine the optimal composition of alkaline earth metal alloys based on silicon in the refining of ferrocarbon melts and modification of non-metallic inclusions. The ionic-molecular complexes of magnesium, oxygen and silicon are constructed in the work, which determine the mechanism of formation of non-metallic inclusions (magnesium silicates) in steel when using silicomagnesium alloys for refining. The parameters of chemical bonding for oxides with ionic bond type, for liquid silicomagnesium alloys having a metallic type of chemical bonding and for hard alloys with metal-covalent bond are determined. The presented results of structural and chemical analysis of the duplex system MgO–SIO2–Mg–Si allow to reveal the mechanisms of desulfurization processes and to develop technologies of blast furnace desulfurization in smelting and ladle treatment with furnace slag, magnesium and its alloys with silicon. Keywords: polygonal diagram, magnesium oxides, alkaline earth metal silicides, quantum mechanical parameters, classification and structuring.