Free energy of melts and intermetallic compounds of binary alloys determined by a molecular dynamics approach.
Free energy of melts and intermetallic compounds of binary alloys determined by a molecular dynamics approach.
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通过分子动力学方法确定二元合金熔体和金属间化合物的自由能
DOI：
10.1103/physreve.89.023308
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Guerdane
中科院分区：
文献类型：
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作者：
M. Guerdane
我们提出了一种原子论的方法，旨在确定二元合金液体的自由能，一个量，它决定了相变的热力学，其评估一直是建模方法的挑战。我们的方法，说明在这里的金属系统模型NiZr，结合两种方法：准谐波近似，适用于一些现有的（真实的或假设的）金属间化合物，和液-固共存条件。的基本方程求解的次正则解近似。我们证明了我们计算的自由能在确定二元体系的相图和定量描述的生长动力学的高可靠性。后一个问题是通过将分子动力学模拟相场建模方面的定向凝固和熔化的两相系统[NiZr]-Zrout的化学平衡说明。
We present an atomistic approach aimed at determining the free energyof binary alloy liquids, a quantity which governs the thermodynamics of phase transformations and whose evaluation has long been a challenge to modeling methods. Our approach, illustrated here for a metallic system model NiZr, combines two methods: the quasiharmonic approximation, applied for some existing (real or hypothetical) intermetallic compounds, and the liquid-solid coexistence conditions. The underlying equations forare solved by means of a subregular-solution approximation. We demonstrate the high reliability of our calculated free energies in determining the phase diagram of a binary system and describing quantitatively the growth kinetics. The latter issue is illustrated by linking molecular dynamics simulations to phase-field modeling with regard to directional solidification and melting in a two-phase system [NiZr]-Zrout of chemical equilibrium.