To illustrate the phase equilibria of an alloy of these three metals, I have pasted the eutectic diagrams of the previous section to the faces of a triangular prism, as shown below. The surface goes d...To illustrate the phase equilibria of an alloy of these three metals, I have pasted the eutectic diagrams of the previous section to the faces of a triangular prism, as shown below. The surface goes down to a deep well, terminating in a eutectic temperature well below the 125 ºC of the Pb-Bi eutectic. Eventually the solidification parts spread out from the corners of the triangle, and meet at a single eutectic point where there are no degrees of freedom.
