Phase equilibria were established in the Nb-Fe-Sb ternary system for an iso
thermal section at 600 degrees C, Investigation of the phase relations was
based on light optical microscopy, electron probe microanalysis, and X-ray
diffraction experiments on are-melted bulk alloys, which were annealed up t
o 1400 h, One ternary compound was observed: NbFeSb (MgAgAs type) without a
significant homogeneity region at 600 degrees C. Except for NbFe2-y, mutua
l solid solubilities at 600 degrees C were found to be very low for example
,<1 at.% re and <1 at.% Nb in the binary Nb antimonides and Fe antimonides,
respectively. The binary Laves phase NbFe2-y with the MgZn2 type exhibits
an extended homogeneity region dissolving at 600 degrees C up to 7 at. % Sb
in the ternary without change of its structure type.