2002 Volume 43 Issue 4 Pages 688-693
In this paper the solidification behavior and phase stability in Nb–W–Si alloys near the Nb–W binary are described. A partial liquidus surface projection of the Nb–W–Si system is constructed based on the observations of microstructure evolution during solidification. Microstructural and microchemical evidences prove the existence of the following eutectic and peritectic reactions: L→β(Nb, W)5Si3+Nbss;L+β(Nb, W)5Si3→(Nb(W))3Si; L→(Nb(W))3Si+Nbss. One invariant point for reaction of L+β(Nb, W)5Si3→(Nb(W))3Si+Nbss is determined near composition Nb–16Si–3W. Moreover, phase stabilities at 1773 K in these alloys are briefly described by identifying the constituent phases after prolonged annealing treatment.