Phase Diagram

Phase Diagram

Phase Diagram


Phase Diagram

It is a graph obtained by plotting one degree of freedom against another. If the phase diagram is plotted between temperature against pressure, the diagram is called P-T diagram. P-T diagram is used for one component system.
If the phase diagram is drawn between temperature against composition, the diagram is called T-C diagram. T-C diagram is used for two component system.

From the phase diagram, it is possible to predict whether an eutectic alloy or a solid solution is formed on cooling a homogeneous liquid containing mixture of two metals. Phase diagrams are useful in understanding the properties of materials in the heterogeneous equilibrium system.

Uses of Phase Diagram

Followings are main uses of phase diagram-
1. From the phase diagram, it is possible to predict whether an eutectic alloy or a solid solution is formed on cooling a homogeneous liquid containing mixture of two metals.
2. The phase diagrams are useful in understanding the properties of materials in the heterogeneous equilibrium system.
3. The study of low melting eutectic alloys, used in soldering, can be carried out using phase diagrams.

Phase Diagram of Water System

Phase Diagram of KI-Water System

Phase Diagram of Lead-Silver System

Phase Rule