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Title: Effects of the inert phase on solidification near a triple-phase line
The local temperature solution near the triple-phase line of a solidifying front, its melt, and a surrounding inert phase was obtained analytically including all three phases and solidification kinetics. This analytical solution was validated using a three-phase numerical model of the horizontal ribbon growth of silicon and compared to a two-phase analysis that models the effect of the third phase (e.g. the gas) as an applied heat flux. Although the three-phase solutions have additional modes to represent the gas behavior, for many conditions the two-phase and three-phase models predicted consistent behaviors. However, introduction of a non-zero growth angle causes the gas phase heat fluxes to have strong gradients near the triple-phase line. Even with zero growth angle, there are conditions in which the two-phase and three-phase solutions are very different; one predicting infinite heat fluxes while the other predicts finite fluxes. This depended on the ratios of thermal conductivities, and the angle at which the solid-melt interface intersected the free surface. In particular, when the thermal conductivity of the inert phase was comparable to the melt or solid phases there were significant differences.  more » « less
Award ID(s):
2317674
PAR ID:
10528507
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Crystal Growth
Volume:
625
Issue:
C
ISSN:
0022-0248
Page Range / eLocation ID:
127438
Subject(s) / Keyword(s):
computer simulation heat transfer interfaces solidification triple-phase line growth from melt
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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