OPTIMIZATION OF THE BINARY GE-RU SYSTEM

After an experimental study of its phase equilibria by DTA and XRD and thermodynamic properties by direct synthesis calorimetry, the Ge-Ru s ystem has been numerically assessed with help of the program Nancy Un. The experimental enthalpies of formation are: Ge0.6Ru0.4:Delta(f) H(1 173 K) = -34.8 (+/-1.0) kJ/mol-atoms Ge0.5Ru0.5:Delta(f) H(1173 K) = - 28.7 (+/-1.3) kJ/mol-atoms The comparison between computation and expe rimental results leads to new ideas about this system. The liquid phas e cannot be described perfectly with a polynomial expansion to the thi rd power, and it seems that associations could explain this behavior.