Eutectic arrest

Eutectic arrest In a cooling (or heating) curve an approximately exothermal segment corresponding to the time interval during which the heat of transformation from the liquid phase of two or more conjugate solid phases is being evolved (or conversely). 

On the other hand, the period of constant temperature for the eutectic point c is greatest in the case of solutions having the same initial composition as the eutectic mixture and it decreases the more the initial composition approaches that of the pure component a or the compound e. In this way we obtain the time-composition curve a c e Here also the point e represents the composition of the compound. We see, therefore, that from the graphic representation of the freezing-point curve, and from the duration of the temperature-arrests on the cooling curve, for solutions of different initial composition, it is possible, without having recourse to analysis, to decide what solid phases are formed, and what is their composition. 

The boride based on Fc3B was identified after rapid solidification as a constituent of metastable eutectic (Fe) + Fc3B [1995Go1, 1982Ber]. However, no thermal arrest of M3B separation was found in [1982Ber] before melting. 

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