THE CONSTITUTION OF THE RUTHENIUM TELLURIUM SYSTEM

The constitution of the Ru-Te system was investigated in the concentra tion range 0-70 at% Te between 400 and 1200-degrees-C using metallogra phy, X-ray diffraction, X-ray microanalysis and differential thermal a nalysis. Only one intermediate compound, RuTe2, exists in the system c rystallizing in the metastable marcasite type at low temperatures and in the pyrite type at high temperatures. The transition is monotropic at about 470-degrees-C in equilibrium with Ru and below 440-degrees-C in equilibrium with Te. RuTe2 is hyperstoichiometric and has a narrow homogeneity region which ranges between 67.3 and 67.8 at% Te. The comp ound decomposes at 1175-degrees-C and 1 bar into Ru and gaseous Te. Th e maximum Te solubility in Ru is 0.13 at% Te at 1000-degrees-C.