Stability of three-phase ternary-eutectic growth patterns in thin sample
Stability of three-phase ternary-eutectic growth patterns in thin sample
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DOI：
10.1016/j.actamat.2016.01.065
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发表时间：
2016-05-01
期刊：
影响因子：
9.4
通讯作者：
Akamatsu, Silvere
中科院分区：
文献类型：
--
作者：
Bottin-Rousseau, Sabine;Serefoglu, Melis;Akamatsu, Silvere
近共晶三元合金在薄试样定向凝固过程中可以表现出ABAC重复单元的稳定周期性生长模式，其中A、B和C是在共晶点与液相平衡的三个固相。我们提出了一个在原位实验研究的动态特性，这样的图案在近共晶In-In 2Bi-Sn合金。我们证明，ABAC模式有一个广泛的稳定范围内的间距λ在给定的增长率。我们定量地研究了负责稳定区间内的稳态图案的间距均匀性的扩散过程。不稳定的过程，确定该区间的限制进行检查。定性，我们表明，三元共晶ABAC模式基本上具有相同的动力学特征，两相二元共晶模式。然而，层消除（低λ稳定性极限）发生在任何埃克豪斯不稳定性表现出来之前。我们还报告了具有[AB]（m）[AC]（n）超结构的固定模式的观测结果，其中m和n是大于1的整数。(C)2016 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Near-eutectic ternary alloys subjected to thin-sample directional solidification can exhibit stationary periodic growth patterns with an ABAC repeat unit, where A, B, and C are the three solid phases in equilibrium with the liquid at the eutectic point. We present an in-situ experimental study of the dynamical features of such patterns in a near-eutectic In-In2Bi-Sn alloy. We demonstrate that ABAC patterns have a wide stability range of spacing lambda at given growth rate. We study quantitatively the lambda-diffusion process that is responsible for the spacing uniformity of steady-state patterns inside the stability interval. The instability processes that determine the limits of this interval are examined. Qualitatively, we show that ternary-eutectic ABAC patterns essentially have the same dynamical features as two-phase binary-eutectic patterns. However, lamella elimination (low-lambda stability limit) occurs before any Eckhaus instability manifests itself. We also report observations of stationary patterns with an [AB](m)[AC](n) superstructure, where m and n are integers larger than unity. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.