Kinetic Monte Carlo modelling of Helium Bubble Nucleation onto Oxides in the Fe-Ti-Y-O System

氦气泡对铜中刃型位错迁移率的影响

Effect of helium bubbles on the mobility of edge dislocations in copper

本研究通过分子动力学模拟探究铜中氦气泡压力对刃型位错迁移的影响，发现高压氦气泡因位错形成超级割阶阻碍强度更低，提取的激活能等参数可支撑多尺度模型扩展。

Friedel oscillations and helium bubble ordering in molybdenum

Helium ions implanted into metals can evolve into ordered bubbles isomorphic to the host lattice. Long-range elastic interaction is generally believed to drive the formation of bubble superlattice, but little is known about the thermodynamics at the very initial stage. Our first-principles calculations demonstrate that in molybdenum, Friedel oscillations induced by individual helium generate both potential barriers and wells for helium clustering at short He-He distances. Such repulsion and attraction at high concentration provide a thermodynamic diving force to assist lining up randomly distr…

金属氚化物中氦泡生长速率的预测

Predicting the growth rate of helium bubbles in metal tritide

氦泡在金属或金属氚化物中的成核和生长是核工业界长期关注的问题，但其机理至今仍不清楚，氦泡生长速率的预测至今仍是空白。本文建立了氦泡在金属氚化物中成核和长大的动力学模型，该模型描述了室温下氦泡在钛氚化物中的直径随t ~（**）（1/3）线性增加，与实验现象符合得很好。通过将存储温度从300 K降低到225 K或将氦原子扩散势垒从0.81 eV提高到1.1 eV的方法，可以有效地抑制气泡的生长，延长氚化钛的寿命4倍以上，为相关实验探索和应用提供了有益的参考。该模型也可用于核工业中新型贮氚材料和面向等离子体材料的寿命预测。

金减缓铁中氦泡的生长

Gold slows down the growth of helium bubble in iron

我们用第一性原理计算预言，在体心立方结构的Fe中，Au对He有很强的亲合力。在He气泡表面的分离Au层中的Au-Au键合比Fe-Fe和Au-Fe相互作用强;因此该层成为进一步He的有效屏障并减缓气泡生长。

铈对铁中氦泡生长的阻碍作用

Impeding effect of cerium on the growth of helium bubble in iron

我们的第一性原理密度泛函理论计算表明，在体心立方Fe中，稀土元素Ce对He的吸引力（-1.31eV）比He-He的吸引力（-1.18eV）强。因此，移动的He原子可以被钉扎到Ce上，从而减少了He团簇的合并。此外，我们发现，分离的Ce层在He气泡表面提出了一个能量势垒为0.33 eV的即将到来的He原子，从而减缓气泡的生长。

Hydrogen bubble nucleation by self-clustering: Density Functional Theory and statistical models studies using tungsten as a model system

Low-energy hydrogen irradiation is known to induce bubble formation in tungsten, while its atomistic mechanisms remain little understood. Using first-principles calculations and statistical models, we studied the self-clustering behavior of hydrogen in tungsten. Unlike previous speculations that hydrogen self-clusters are energetically unstable owing to the general repulsion between two hydrogens, we demonstrated that hydrogen self-cluster becomes more favorable as the cluster size increases. We found that hydrogen atoms would form two-dimensional platelet-like structures along {100} planes. T…