Figure 5. Comparison of vapor pressures (log₁₀ P versus 1/T) calculated from heat of formation and thermodynamic data with published values obtained in high-temperature equilibrium measurements.

(a) 4AlN(c) + 3C(c) → Al₄C₃(c) + 2N₂(g): A and A′ calculation from thermal data,* A′′ = Prescott and Hincke [36].

(b) Al₄C₃(c) → 4Al(g) + 3C(c): B and B′ = calculation from thermal data,* B′′ = Meschi and Searcy [31], ○ = Chupka et al. [34], Δ = Campbell [35].

(c) 2Al₂O₃(c) + 9C(c) = Al₄C₃(c) + 6CO(g): C and C′ calculation from thermal data,*

C′′ = Prescott and Hincke [37], C′′′ = Brunner [38].

C^I = Al₄O₄C(c) + 6C(c) → Al₄C₃(c) + 4CO(g): Cox and Pidgeon [40].

C^II = 2Al₂O₃(c) + 3C(c) → Al₄O₄C(c) + 2CO(g): [40].

C^III = Al₂O₃(c) + 3C(c) → Al₂OC(c) + 2CO(g): [40].

(d) 8MgO(c) + Al₄C₃(c) → 2MgAl₂O₄(c) + 3C(c) + 6Mg(g): D and D′ = calculation from thermal data, D′′ = Grjotheim et al. [41].