Binary Alloy Thermodynamics

Regular solution model — Gibbs free energy of mixing, spinodal & binodal

Parameters

Theory

Regular solution model:
ΔH_mix = Ω·x(1−x)
ΔS_mix = −R[x ln x + (1−x)ln(1−x)]
ΔG_mix = ΔH_mix − TΔS_mix

Spinodal: d²G/dx² = 0
Binodal: common tangent

Critical point:
T_c = Ω/2R, x_c = 0.5

Miscibility gap: T < T_c
T_c: --
Phase: --