Phases in iron-carbon alloys
Phase is a homogeneous part of the system, separated from another interface, when passing through which the composition, structure and properties change abruptly.
Depending on the physicochemical interaction of the alloy components, the following phases may form: liquid solutions, solid solutions, and chemical compounds.
The iron-carbon system alloys are characterized by all the listed options:
1) the liquid phase;
2) ferrite (solid solution of the introduction of carbon in the α-iron);
3) austenite (solid solution of the introduction of carbon in the γ-iron);
4) cementite (chemical compound).