Comparing the accuracy of melting temperature prediction methods for high entropy alloys
Comparing the accuracy of melting temperature prediction methods for high entropy alloys
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DOI：
10.1063/5.0101548
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发表时间：
2022-11
影响因子：
3.2
通讯作者：
Saswat Mishra;Karthik Guda Vishnu;A. Strachan
中科院分区：
文献类型：
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作者：
Saswat Mishra;Karthik Guda Vishnu;A. Strachan
难熔复合浓缩合金（RCCA）是一类相对较新的材料，可以在高温下表现出优异的机械性能，确定其熔化温度（Tm）对于评估其工作范围至关重要。不幸的是，这个属性的实验测定是具有挑战性的和计算工具来预测的第一原理计算的RCCA的Tm是非常可取的。我们量化的不确定性与这种预测的两种方法，可以使用基于密度泛函理论的分子动力学和应用它们来预测等原子NbMoTaW的熔化温度。我们发现，结合自由能计算的各个阶段的动态共存的方法可以提供准确的结果，尽可能少的计算成本。我们预测RCCA NbMoTaW的熔化温度在3000和3100 K之间。
Refractory complex concentrated alloys (RCCAs) are a relatively new class of materials that can exhibit excellent mechanical properties at high temperatures, and determining their melting temperature ( Tm) is critical to assess their range of operation. Unfortunately, the experimental determination of this property is challenging and computational tools to predict the Tm of RCCAs from first-principles calculations are highly desirable. We quantify the uncertainties associated with such predictions for two methods that can be used with density functional theory-based molecular dynamics and apply them to predict the melting temperature of equiatomic NbMoTaW. We find that a combination of free energy calculations of individual phases with a dynamical coexistence method can provide accurate results with the minimum possible computational cost. We predict the melting temperature for the RCCA NbMoTaW to be between 3000 and 3100 K.