VNbCrMo refractory high-entropy alloy for nuclear applications
VNbCrMo refractory high-entropy alloy for nuclear applications
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DOI：
10.1016/j.ijrmhm.2023.106200
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发表时间：
2023-03-20
影响因子：
3.6
通讯作者：
Knowles, A. J.
中科院分区：
文献类型：
--
作者：
Ferreiros, P. A.;von Tiedemann, S. O.;Knowles, A. J.
具有高熔点和低中子吸收截面的难熔高熵合金（RHEAs）被寻求用于第四代裂变和聚变反应堆。使用高通量计算筛选工具Alloy Search and Predict（ASAP）从超过100万个四元素等摩尔组合中鉴定有希望的RHEA候选物。通过CALPHAD进一步研究了选定的VNbCrMo RHEA以预测相形成，并与实验生产的在1200 ℃时效的铸锭进行了比较。VNbCrMo RHEA被发现构成一个主要的体心立方相，与6%的面积分数的C15-Laves形成在枝晶间区域，在单相的预测相反。基于刃位错机制的模型的屈服强度的预测表明，在室温下为2.1 GPa，在1000 ℃下为850 MPa，对于等摩尔的单一bcc相。具有C15-Laves的合金的硬度为748 HV（屈服强度-2.4GPa）。最后，宏观中子吸收截面的模拟范围很广的能量。在典型的聚变和裂变反应堆情景中，使用清单代码FISPACT-II进行了连续运行2年后长达1000年的每年每个原子的位移和活化计算。这项工作提供了新的洞察VNbCrMo RHEA的相稳定性和性能，这是一个类似的设计概念合金进行比较，以评估潜在的新型RHEA用于先进的核应用。
Refractory high-entropy alloys (RHEAs) with high melting points and low neutron absorption cross-section are sought for generation-IV fission and fusion reactors. A high throughput computational screening tool, Alloy Search and Predict (ASAP), was used to identify promising RHEA candidates from over 1 million four-element equimolar combinations. The selected VNbCrMo RHEA was further studied by CALPHAD to predict phase for-mation, which was compared to an experimentally produced ingot aged at 1200 degrees C. The VNbCrMo RHEA was found to constitute a majority bcc phase, with a 6% area fraction of C15-Laves formed at interdendritic regions, in contrast to the predictions of single-phase. The prediction of the yield strength by a model based upon edge dislocation mechanisms indicated 2.1 GPa at room temperature and 850 MPa at 1000 degrees C for the equimolar single bcc phase. The hardness of the alloy with C15-Laves was 748 HV (yield strength-2.4 GPa). Finally, the macroscopic neutron absorption cross-section was modelled for a wide range of energies. Displacements per atom per year and activation calculations, up to 1000 years after 2 years of continuous operation, in typical fusion and fission reactor scenarios were also performed using the inventory code FISPACT-II. This work gives new insight into the phase stability and performance of the VNbCrMo RHEA, which is compared with a similar design concept alloy, to assess the potential of novel RHEAs for use in advanced nuclear applications.