What is an eutectic point, and what are the three states of a eutectic point?
A eutectic or eutectic mixture is a mixture of two or more phases at a composition that has the lowest melting point, and where the phases simultaneously crystallise from molten solution at this temperature. The proper ratios of phases to obtain a eutectic is identified by the eutectic point on a phase diagram. The term comes from the Greek ‘eutektos’, meaning ‘easily melted.’ The phase diagram at right displays a simple binary system composed of two components, A and B, which has a eutectic point. The phase diagram plots relative concentrations of A and B along the X-axis, and temperature along the Y-axis. The eutectic point is the point at which the liquid phase borders directly on the solid α + β phase (A solid phase composed of both A and B), representing the minimum melting temperature of any possible alloy of A and B. The temperature that corresponds to this point is known as the eutectic temperature. Not all binary system alloys have a eutectic point: those that form a solid sol
