通过辐照诱导偏析控制聚变钢中氦泡处的氢同位素滞留
Controlling Hydrogen Isotope Retention at Helium Cavities through Radiation-Induced Segregation in Fusion Steels
- University of Michigan（密歇根大学）
- Wuhan University（武汉大学）
- Oak Ridge National Laboratory（橡树岭国家实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究通过实验和计算揭示辐照诱导的Cr和Ta偏析至氦泡表面，增强氢同位素结合能并提高迁移势垒，从而增加滞留，为聚变钢中控制氚库存提供合金设计策略。
AI中文摘要：
氢同位素在面向等离子体和结构合金中的滞留是氘-氚聚变面临的核心材料挑战。受离子束辐照实验和第一性原理计算的启发，我们识别出一种辐照驱动的机制，即溶质向缺陷阱的偏析增强了氢同位素的捕获。对低活化铁素体-马氏体钢F82H进行的三束离子辐照揭示了Cr和Ta在泡表面的显著偏析。密度泛函理论表明，这些偏析物通过增强结合能和增加迁移势垒，显著提高了H在泡处的稳定性，导致滞留量大幅增加。该效应源于溶质调控的电子结构：Ta促进了强的H 1s-金属d轨道杂化，而Cr则将表面d带移向更有利的成键构型。这些发现为辐照诱导偏析与高温氢同位素滞留之间提供了原子层面的联系，并为在聚变环境中控制氚库存提供了合金化学途径。
英文摘要：
Hydrogen isotope retention in plasma facing and structural alloys is a central materials challenge for deuterium-tritium fusion. Motivated by ion beam irradiation experiments and first principles calculations, we identify an irradiation-enabled mechanism whereby solute segregation to defect sinks enhances hydrogen isotope trapping. Triple-ion irradiation of reduced activation ferritic-martensitic steel F82H reveals pronounced segregation of Cr and Ta to cavity surfaces. Density functional theory shows that these segregants markedly increase H stability at cavities by strengthening binding energies and increasing migration barriers, leading to substantially higher attention. The effect originates from solute-tuned electronic structure: Ta promotes strong H 1s-metal d orbital hybridization, whereas Cr shifts the surface d-band toward a more favorable bonding configuration. These findings provide an atomistic link between irradiation-induced segregation and elevated-temperature hydrogen isotope retention and alloy chemistry routes to control tritium inventory in fusion environments.
