Eutectic system
![A phase diagram for a fictitious binary chemical mixture (with the two components denoted by A and B) used to depict the eutectic composition, temperature, and point. (L denotes the liquid state.)](/Images/godic/202501/12/Eutectic_system_phase_diagram.svg3824.png")
![Four eutectic structures: A) lamellar B) rod-like C) globular D) acicular.](/Images/godic/202501/12/Various_eutectic_structures3824.png")
![Solid-liquid phase change of ethanol water mixtures](/Images/godic/202501/12/Phase_diagram_ethanol_water_s_l_en.svg3824.png")
![Iron-carbon phase diagram, showing the eutectoid transformation between austenite (γ) and pearlite.](/Images/godic/202501/12/Steel_pd.svg3824.png")
A eutectic system (US dict: yü-'tek-tik) from the Greek "ευ" (eu = easy) and "Τήξις" (teksis = melting) describes a homogeneous solid mix of atomic and/or chemical species, to form a joint super-lattice, by striking a unique atomic percentage ratio between the components — as each pure component has its own distinct bulk lattice arrangement. It is only in this atomic/molecular ratio that the eutectic system melts as a whole, at a specific temperature (the eutectic temperature) the super-lattice releasing at once all its components into a liquid mixture. The eutectic temperature is the lowest possible melting temperature over all of the mixing ratios for the involved component species.