Ab initio study of tungsten-based alloys under fusion power-plant conditions
Ab initio study of tungsten-based alloys under fusion power-plant conditions
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DOI：
10.1016/j.jnucmat.2023.154422
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发表时间：
2023-04
影响因子：
3.1
通讯作者：
Yichen Qian;M. Gilbert;L. Dezerald;D. Nguyen-Manh;D. Cereceda
中科院分区：
文献类型：
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作者：
Yichen Qian;M. Gilbert;L. Dezerald;D. Nguyen-Manh;D. Cereceda
钨被认为是未来聚变能源装置中结构和功能材料的主要候选者。钨的高熔点、高热导率、低溅射产额和低长期处置放射性足迹是磁聚变和惯性聚变能源反应堆最吸引人的特性。然而，钨的断裂韧性也很低，主要与晶间破坏和块体塑性有关，限制了其应用。近年来，为了克服纯钨的上述局限性，人们开发了几个系列的钨基合金。这可能包括钨基高熵合金(W-HEAs)和减少热氧化的钨基自钝化金属合金或“智能合金”(W-SAS)。考虑到它们接近等离子体，了解这些候选面向等离子体的材料(PFM)暴露在聚变反应堆中预期的中子通量中是如何随着时间的推移影响其材料行为的至关重要的。在这项工作中，我们提出了一种结合清单编码和第一性原理密度泛函电子结构计算的计算方法来理解转变的钨基PFM的行为。特别是，我们计算了五种钨基PFM在Eu-Demo聚变第一壁条件下暴露十年时的化学成分、生产不确定性、弹性和延展性以及态密度的变化。
Tungsten (W) is considered a leading candidate for structural and functional materials in future fusion energy devices. The most attractive properties of tungsten for magnetic and inertial fusion energy reactors are its high melting point, high thermal conductivity, low sputtering yield, and low long-term disposal radioactive footprint. However, tungsten also presents a very low fracture toughness, primarily associated with inter-granular failure and bulk plasticity, limiting its applications. In recent years, several families of tungsten-based alloys have been explored to overcome the aforementioned limitations of pure tungsten. These might include tungsten-based high-entropy alloys (W-HEAs) and tungsten-based Self-passivating Metal Alloys with Reduced Thermo-oxidation or “SMART alloys” (W-SAs). Given their proximity to the plasma, it is crucial to understand how the exposure of these candidate plasma-facing materials (PFMs) to the neutron fluxes expected in fusion reactors impacts their material behavior over time. In this work, we present a computational approach that combines inventory codes and first-principles DFT electronic structure calculations to understand the behavior of transmuting tungsten-based PFMs. In particular, we calculate the changes in the chemical composition, production uncertainties, the elastic and ductility properties, and the density of states for five tungsten-based PFMs when exposed to EU-DEMO fusion first wall conditions for ten years.