ANALYSTS OF NONEQUILIBRIUM SOLIDIFICATION OF SUBEUTECTIC SILLUMINES USING MULTICOMPONENT PHASE-DIAGRAMS

A method has been proposed for analyzing the formation of cast structure in ternary and quaternary sillumines during nonequilibrium solidification. The method uses the equilibrium phase diagrams in the assumption that the peritectic reactions are suppressed and the eutectic reactions occur in accordance with the phase diagram. A possible mechanism whereby cooling rate affects the sequence of phase solidification has been suggested. The Al-Si-Fe, Al-Si-Cu-Mg, and Al-Si-Mg-Fe systems have been analyzed as examples. The method enables investigation of the real phase composition of cast sillumines.