Physics – Condensed Matter – Materials Science
Scientific paper
2000-05-29
Phys. Rev. E 63, 031504 (2001)
Physics
Condensed Matter
Materials Science
Final version, minor revisions, 16 pages, 14 EPS figures, RevTeX
Scientific paper
10.1103/PhysRevE.63.031504
During the directional solidification of peritectic alloys, two stable solid phases (parent and peritectic) grow competitively into a metastable liquid phase of larger impurity content than either solid phase. When the parent or both solid phases are morphologically unstable, i.e., for a small temperature gradient/growth rate ratio ($G/v_p$), one solid phase usually outgrows and covers the other phase, leading to a cellular-dendritic array structure closely analogous to the one formed during monophase solidification of a dilute binary alloy. In contrast, when $G/v_p$ is large enough for both phases to be morphologically stable, the formation of the microstructurebecomes controlled by a subtle interplay between the nucleation and growth of the two solid phases. The structures that have been observed in this regime (in small samples where convection effect are suppressed) include alternate layers (bands) of the parent and peritectic phases perpendicular to the growth direction, which are formed by alternate nucleation and lateral spreading of one phase onto the other as proposed in a recent model [R. Trivedi, Metall. Mater. Trans. A 26, 1 (1995)], as well as partially filled bands (islands), where the peritectic phase does not fully cover the parent phase which grows continuously. We develop a phase-field model of peritectic solidification that incorporates nucleation processes in order to explore the formation of these structures. Simulations of this model shed light on the morphology transition from islands to bands, the dynamics of spreading of the peritectic phase on the parent phase following nucleation, which turns out to be characterized by a remarkably constant acceleration, and the types of growth morphology that one might expect to observe in large samples under purely diffusive growth conditions.
Karma Alain
Lo Tak Shing
Plapp Mathis
No associations
LandOfFree
Phase-field modeling of microstructural pattern formation during directional solidification of peritectic alloys without morphological instability does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Phase-field modeling of microstructural pattern formation during directional solidification of peritectic alloys without morphological instability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase-field modeling of microstructural pattern formation during directional solidification of peritectic alloys without morphological instability will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-257064