8: Critical evaluation of constitution of iron-silicon-vanadium system

Abstract

A critical assessment has been made of the available experimental information on the con-l stitution of the Fe-Si-V system, which is of interest in connection with the relationships of the ternary phases formed with those in other ternary systems. The assessment reveals considerable uncertainty with regard to the equilibrium relationships involved. Thus, though primary crystallization of at least one ternary phase has been reported, in the solid state three such phases exist. The manner in which the latter are formed is open to considerable doubt. The liquidus surfaces reported in the literature are presented and discussed, together with liquidus temperature contours. Evidence for the equilibrium in the solid state is presented in the form of isothermal diagrams. Although the formation of three ternary phases appears certain, disagreements in the literature with regard to the equilibria in which they may be involved are pointed out. Much more experimental information is required, and it may be noted that no data are available below 1000°C.