A Fast and Robust Method for Predicting the Phase Stability of Refractory Complex Concentrated Alloys using Pairwise Mixing Enthalpy
A Fast and Robust Method for Predicting the Phase Stability of Refractory Complex Concentrated Alloys using Pairwise Mixing Enthalpy
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DOI：
10.1016/j.actamat.2022.118389
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发表时间：
2022-10-18
期刊：
影响因子：
9.4
通讯作者：
Mishra，Rohan
中科院分区：
文献类型：
--
作者：
Zhang，Zhaohan;Li，Mu;Mishra，Rohan
预测难熔复杂浓缩合金（RCCAs）的成分和温度依赖稳定性的能力对高温结构合金的设计至关重要。在这里，我们提出了一个基于第一性原理计算的模型，以高通量的方式预测多组分等摩尔固溶体的热力学稳定性，并将其应用于筛选超过20,000种组合物。我们利用密度泛函理论（DFT）建立了一个包含17种难熔金属的成对混合焓的数据库。针对这些问题，我们拟合了能够准确捕捉多组分BCC固溶体混合焓的热力学溶液模型。通过将它们的能量与dft计算的材料项目数据库中的金属间化合物的焓进行比较，并使用凸包分析，我们确定了任何RCCA的稳定相作为温度的函数。预测的NbTiZr、NbTiZrV和NbTiZrVM（M=Mo,Ta,Cr）体系的稳定性随温度的变化规律与实验结果一致。我们应用该模型预测了NbVZr-Tix（0 <x <1）的相演化，并通过高通量激光沉积合成技术进行了实验验证。该方法提供了一种快速准确的方法来估计新型rcca的相稳定性，从而加快了它们的实验发现。
The ability to predict the composition- and temperature-dependent stability of refractory complex concentrated alloys (RCCAs) is vital to the design of high-temperature structural alloys. Here, we present a model based on first-principles calculations to predict the thermodynamic stability of multicomponent equimolar solid solutions in a high-throughput manner and apply it to screen over 20,000 compositions. We develop a database that contains pairwise mixing enthalpy of 17 refractory metals using density-functional theory (DFT)-based total energy calculations. To these, we fit thermodynamic solution models that can accurately capture the mixing enthalpy of multicomponent BCC solid solutions. By comparing their energy with DFT-calculated enthalpy of intermetallics from the Materials Project database and using convex hull analyses, we identify the stable phase of any RCCA as a function of temperature. The predicted stability of NbTiZr, NbTiZrV, and NbTiZrVM(M=Mo,Ta,Cr) systems as a function of temperature agree well with prior experimental observations. We apply our model to predict the phase evolution in NbVZr-Tix(0 <x <1), which is confirmed experimentally using a high-throughput, laser deposition-based synthesis technique. This method provides a fast and accurate way to estimate the phase stability of new RCCAs to expedite their experimental discovery.