The isothermal section phase diagram of the La-Fe-Ge ternary system at 773Â K

The isothermal section of the phase diagram of the La-Fe-Ge ternary system at 773 K was investigated by X-ray powder diffraction (XRD), differential thermal analysis (DTA) and optical microscopy. The existences of 12 binary compounds, La3Ge, La5Ge3, La4Ge3, La5Ge4, LaGe, La2Ge3, LaGe2−x, Fe3Ge, Fe5Ge3, Fe6Ge5, FeGe, FeGe2, were confirmed. Three ternary compounds LaFe2Ge2, LaFe0.6Ge2 and LaFeGe3 were confirmed too. Ge in Fe, LaGe, LaGe2−x and Fe5Ge3 and Fe in LaFe0.6Ge2 have solid solution phenomenon. This section consists of 18 single-phase regions, 37 two-phase regions, and 20 three-phase regions.