在 W 中竞争的动力学和气泡形态。

Competing kinetics and he bubble morphology in W.

机构信息

Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.

Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 USA.

出版信息

Phys Rev Lett. 2015 Mar 13;114(10):105502. doi: 10.1103/PhysRevLett.114.105502. Epub 2015 Mar 11.

DOI:10.1103/PhysRevLett.114.105502

PMID:25815946

Abstract

The growth process of He bubbles in W is investigated using molecular dynamics and parallel replica dynamics for growth rates spanning 6 orders of magnitude. Fast and slow growth regimes are defined relative to typical diffusion hopping times of W interstitials around the He bubble. Slow growth rates allow the diffusion of interstitials around the bubble, favoring the biased growth of the bubble towards the surface. In contrast, at fast growth rates interstitials do not have time to diffuse around the bubble, leading to a more isotropic growth and increasing the surface damage.

摘要

使用分子动力学和并行复制动力学研究了 He 泡在 W 中的生长过程，生长速率跨越了 6 个数量级。相对于 W 间隙原子在 He 泡周围的典型扩散跳跃时间，定义了快生长和慢生长两个区域。慢生长速率允许间隙原子在泡周围扩散，有利于泡向表面的偏析生长。相比之下，在快生长速率下，间隙原子没有时间在泡周围扩散，导致更各向同性的生长，并增加表面损伤。