Phase Diagrams

· The phase diagram is for the single component system, carbon, that can exist in four phases in different ranges of (T, p). i.e.: C = 1, P = 4.

· The "full" Gibbs phase rule must be used. (T, p) are the variables:
F = {C - P + 2}
· At (a) (b) (c) (d), only one phase exists: P = 1, and F = 2. In a single phase zone (T, p) are independent variables.
· Points (e), (f) lie on a line that is the locus of equilibrium (T, p) states between two phases. On this line: P = 2, C = 1, and F = 1.

After: Kingery, et al., "Introduction to Ceramics," Wiley (1976)