Experimental determination of the Ta-Ge phase diagram

In the present work, the Ta-Ge phase diagram has been experimentally studied, considering the inexistence of a Ta-Ge phase diagram in the literature. The samples were prepared via arc melting and characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD). The intermetallics phases βTa3Ge, αTa3Ge, βTa5Ge3 and TaGe2 where confirmed in this system. Three eutectics reactions where determined with the liquid compositions at 20.5; 28.0; 97.0 at.% Ge. The phases βTa3Ge and βTa5Ge3 solidifies congruently while TaGe2 is formed through a peritectic transformation. The temperature of the Ta-rich eutectic (L ↔ Tass + βTa3Ge) was measured by the Pirani-Alterthum method at 2440 °C and the Ge-rich eutectic (L ↔ TaGe2 + Gess) by DTA at 937 °C.