Abstract Molecular dynamics simulation is used to systematically investigate mechanical properties of tungsten-hydrogen system and hydrogen diffusion in tungsten. It is found that the tensile strength of tungsten is decreased seriously by the formation of hydrogen bubbles, and the intrinsic mechanism is discussed by deformation dislocations. The present calculation also reveals that the hydrogen clusters in tungsten would be hard to diffuse, and may finally accumulate and form bubbles. In addition, the uniaxial and isotropic tensile strains have different effects on the diffusivity of hydrogen clusters, and the mean square displacements of H clusters diffusing along several directions under uniaxial and isotropic tensile strains are derived and compared with each other. The simulated results agree well with experimental evidence and calculated data available in the literature.

中文翻译：

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钨-氢系统力学性能及氢在钨中扩散的原子模拟

摘要 利用分子动力学模拟系统地研究了钨-氢体系的力学性能和氢在钨中的扩散。发现氢气泡的形成严重降低了钨的抗拉强度，并通过变形位错讨论了其内在机制。目前的计算还表明，钨中的氢簇很难扩散，最终可能会积聚形成气泡。此外，单轴和各向同性拉伸应变对氢团簇扩散率的影响不同，推导出了单轴和各向同性拉伸应变下H团簇沿多个方向扩散的均方位移，并进行了比较。