Phases and Phase Diagrams
Two Component Phase Diagram
How to Read a Phase Diagram: This two-phase diagram features two types of curves. Lines separating partially liquid phases from fully liquid phases are known as liquidis lines while the line separating partially melted phases from solids are known as solidus. The point where all three lines meet (point E in this diagram) is known as the eutectic point. Near the eutectic point, a samples behavior is very dependent on its composition. For example, wetting behavior may differ dramatically between the situation of solid a wetting with liquid b vs solid b wetting with liquid a.
The horizontal axis shows the relative composition between the two phases while the vertical axis indicates the temperature of the system. Melting far from the eutectic point may occur over a range of temperatures between solidus and liquidus where both phases are fully melted.
If one has a mixture of composition X at temperature <math>T_2</math>, the percent of A in solid form would be given as the following: % solid A = b/(a+b)*100. The remaining portion of A in the mixture is melted.