Theory and experiments of interphase formation and structure in horizontal directionally solidified Zn-Al dendritic alloys

Abstract

The aim of this work was to analyze the experimental formation of [liquid/ (solid+liquid)], [(solid+liquid)/(eutectic+solid+liquid)], [(eutectic+solid+liquid)/solid], and [(solid+liquid)/solid] interphases run in binary Zn-Al dendritic alloy systems from the chilled ends of a hemicylindrical sample. We determined the velocity and accelerations of almost six imposed interphases, three of which moved from left to right and three from right to left, in a horizontal setup with chilled ends. We also calculated their velocities and accelerations from the near beginning of the creation until the instant in which they collided with the solidification fronts imposed. Detailed analyses of their structure, which presents the columnar-to-equiaxed transition (CET), and their development with models of dendritic solidification, were also made. These results, combined with the existing data, were compared with theoretical models to assess our current understanding of the dynamics of the interphases in dendritic growth process. This is an important subject within crystal growth science.