Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Advanced Research Systems, Macungie, PA, 18018, USA.
Nat Commun. 2018 Oct 30;9(1):4520. doi: 10.1038/s41467-018-06757-2.
The ability to predict and understand phases in high-entropy alloys (HEAs) is still being debated, and primarily true predictive capabilities derive from the known thermodynamics of materials. The present work demonstrates that prior work using high-throughput first-principles calculations may be further utilized to provide direct insight into the temperature- and composition-dependent phase evolution in HEAs, particularly Al-containing HEAs with a strengthening multiphase microstructure. Using a simple model with parameters derived from first-principles calculations, we reproduce the major features associated with Al-containing phases, demonstrating a generalizable approach for exploring potential phase evolution where little experimental data exists. Neutron scattering, in situ microscopy, and calorimetry measurements suggest that our high-throughput Monte Carlo technique captures both qualitative and quantitative features for both intermetallic phase formation and microstructure evolution at lower temperatures. This study provides a simple approach to guide HEA development, including ordered multi-phase HEAs, which may prove valuable for structural applications.
预测和理解高熵合金(HEAs)中的相仍然存在争议,主要的准确预测能力源自于材料的已知热力学。本工作表明,先前使用高通量第一性原理计算的工作可以进一步用于提供对 HEAs 中温度和成分依赖的相演变的直接洞察,特别是具有强化多相微观结构的含 Al 的 HEAs。使用从第一性原理计算得出的参数的简单模型,我们再现了与含 Al 相相关的主要特征,展示了在实验数据很少的情况下探索潜在相演变的可推广方法。中子散射、原位显微镜和量热法测量表明,我们的高通量蒙特卡罗技术既可以捕捉到较低温度下金属间相形成和微观结构演变的定性特征,也可以捕捉到定量特征。这项研究为指导 HEA 的发展提供了一种简单的方法,包括有序的多相 HEA,这对于结构应用可能是有价值的。