Aug 6, 2017
A metatectic point on a phase diagram, also known as a catatectic point, is an invariant point wherein a single solid phase transitions into a liquid phase as well as a second solid phase (or vice versa). It is similar to a peritectic point, however the single solid phase exists at a higher temperature than the mixture of solid and liquid phases, which is the opposite or a peritectic.
Examples of this behavior (a solid becoming partially liquid) does not typically occur in metallic systems, however it can occur in other instances, such as the phase diagrams of fatty acids.
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