Experimental Investigation of Phase Equilibria in Ti–Zr–Ge System

Phase equilibria in the Ti–Zr–Ge ternary system at 1073 and 1173 K were investigated experimentally using equilibrated alloys with electron probe microanalysis and x-ray diffraction analysis. No ternary compounds were detected. Eleven and nine three-phase regions were determined in the Ti–Zr–Ge isothermal section at 1073 and 1173 K, respectively. Intermediate compounds ZrGe2, Zr5Ge4, Zr5Ge3, Ti5Ge4, and Ti5Ge3, possessing large solubility, extended along the Ge isoconcentration line, indicating remarkable substitution of Ti for Zr in the Zr–Ge compounds or of Zr for Ti in the Ti–Ge compounds. The solubility of Ti in ZrGe2 increased from 16.0 at.% at 1073 K to 19.3 at.% at 1173 K, while that of Zr in Ti5Ge3 remained nearly 41.0 at.% at both 1073 and 1173 K.