16: Critical evaluation of constitution of iron-molybdenum-silicon alloys

Abstract

The constitution of the Fe-Mo-Si system, based on available experimental evidence reinterpreted where necessary in view of recent work, is summarized in the form of a projection of primary surfaces and an isothermal section at 800°C. The system contains two ternary compounds, T₁ (Fe₂MoSi₂) and T₂2 (Mo₃ FeSi), of which only T₁ is formed from the liquid according to present evidence. In the solid state a phase based on Fe₂Mo appears to be stabilized by silicon to higher temperatures than in the binary system, while phases based on the Fe-Mo R-phase and the Fe₅Si₃ phase of the Fe-Si system persist at lower temperatures than in the respective binaries. The data allow the construction of reaction sequences for liquid-solid equilibria and for solid-state reactions. A room-temperature constitution is tentatively suggested.