Lever Rule for the Uranium-Titanium Solid-Liquid Phase Diagram
Lever Rule for the Uranium-Titanium Solid-Liquid Phase Diagram
A solid-liquid phase diagram for the uranium-titanium system shows the regions of phase stability as a function of the temperature and overall composition of the system. The phases are (1) a liquid mixture of uranium and titanium of variable composition, (2) solid uranium , (3) solid titanium , and (4) a solid phase compound with the formula . In this phase diagram, the phase boundaries are shown as solid black lines. The phase boundaries involving liquids are assumed to be a linear function of composition. When the temperature and composition are at a point above all the phase boundaries, only the liquid mixture is stable. At any point inside the phase boundaries, two phases are stable. The phases present, as well as their relative amounts, are shown in the bar graph on the right. When the liquid phase is present, its composition is found by drawing a horizontal line (here shown as a dashed red line) to the appropriate phase boundary. For a solid phase, a horizontal line is drawn (here shown dashed) to the vertical phase boundary corresponding to the pure solid. These horizontal lines are called "tie lines" or "levers". The lever rule is used to calculate the relative amounts of the two phases, which are shown on the bar graph on the right. The composition of the liquid phase is indicated by the red dotted line and numerically at the top of the bar graph.
U
(s)
Ti
(s)
TiU
2(s)