Thermodynamic values for the liquid phase and phase equilibrium data of Cu-
Si available in the literature were analyzed to yield a thermodynamic descr
iption of this system which is an important binary for many multicomponent
technologically important alloys. In contrast to the calculated phase diagr
ams using descriptions available in the literature, the calculated diagram
using the present one agrees with experimental data in terms of the liquidu
s, the solidus and the (Cu) solvus as well as the temperatures and composit
ions of the coexisting phases for 10 invariant equilibria. The calculated e
nthalpy of mixing of the liquid alloys also agrees with experimentally meas
ured values. The intermediate phases epsilon-Cu15Si4, eta-Cu19Si6, gamma-Cu
56Si11 and delta-Cu33Si7 were taken to be fine compounds as were done in al
l previous descriptions. This assumption was made since these phases have r
ather small ranges of homogeneity and they have minimum effects on phases i
n technologically important multicomponent alloys. This improved descriptio
n can be used with confidence to obtain descriptions for higher order alloy
s. (C) 2000 Elsevier Science S.A. All rights reserved.