Kinetics of isothermal phase transformations by phase-field simulations:an analogy between the peritectic and monotectic systems

摘要

We present phase-field simulations of isothermal phase transformations in the peritectic system below and above the peritectic temperature T_p, and in the monotectic system below the monotectic temperature T_M- We focus particularly on the Liquid-Film-Migration (LFM) mechanism, which appears to be the generic process for phase transformations above T_P. Below T_P, we obtain an assymetric LFM, suggesting the existence of a doublon structure in free space. In the monotectic system, the transformation from a liquid L_1 to a solid+liquid L_2 mixture proceeds via the migration of a L_2 film, which is the analogous of the LFM process. When the metastable state consists of a liquid-liquid mixture, a dendritic-like solidification is obtained.