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Your search keyword '"You, Yu"' showing total 17 results
Start Over Author "You, Yu" Journal journal of nuclear materials
17 results on '"You, Yu"'

13. Effect of multiple Ti doping on helium behavior in ZrCo

Author

Yougen Yi, Xianggang Kong, Qingqing Wang, You Yu, Huilei Han, Guanghui Zhang, Ge Sang, and Tao Gao

Subjects
Condensed Matter::Quantum Gases, Nuclear and High Energy Physics, Materials science, Doping, chemistry.chemical_element, 02 engineering and technology, Trapping, 021001 nanoscience & nanotechnology, 01 natural sciences, 010305 fluids & plasmas, Nuclear Energy and Engineering, chemistry, Chemical physics, Vacancy defect, 0103 physical sciences, Physics::Atomic and Molecular Clusters, General Materials Science, Density functional theory, Grain boundary, Physics::Atomic Physics, 0210 nano-technology, Embrittlement, Ti doping, Helium
Abstract

Helium can cause segregation of solute atoms in the material, and in turn, the segregated solute atoms will have a great influence on the behavior of helium. Studying the behavior of helium in tritium storage materials is very important for the design of materials with strong helium retention capacity. In this paper, the first-principles method based on density functional theory is used to study the segregation of doped atoms Ti caused by defects (He atoms) in ZrCo system, and the effect of segregated Ti atoms on He behavior. The effect of segregated Ti atoms on the stability of He atoms was explored. The CI-NEB method was used to simulate the variance of the trapping for He atoms by vacancy in the pure and doped systems. Finally, it was found that the number of He atoms trapped by the vacancy is reduced due to the Ti cage. In addition, the Ti cage has a certain pinning effect on He atoms. In short, the segregated Ti inhibits the migration of He and hinders the flow of He to the grain boundaries, thereby suppressing the helium embrittlement effect.

Published
2021

16. The stability of vacancy clusters and their effect on helium behaviors in 3C-SiC.

Author

You, Yu-Wei, Xu, Yichun, Liu, C.S., Fang, Q.F., Sun, Jingjing, Hou, Jie, Li, B.S., and Wang, Z.G.

Subjects
*SILICON carbide, *HELIUM atom, *ELECTRON density, *FUSION reactors, *NUCLEAR reactors
Abstract

We have carried out systematical ab initio calculations to study the stability of vacancy clusters and their effect on helium behaviors in 3C-SiC. It is found that the formation energies of vacancy clusters containing only carbon vacancies are the lowest although the vacancies are not closest to each other, while the binding energies of vacancy clusters composed of both silicon and carbon vacancies in the closest neighbors to each other are the highest. Vacancy clusters can provide with free space for helium atoms to aggregate, while interstitial sites are not favorable for helium atoms to accumulate. The binding energies of vacancy clusters with helium atoms increase almost linearly with the ratio of helium to vacancy, n / m . The binding strength of vacancy cluster having the participation of the silicon vacancy with helium is relatively stronger than that without silicon vacancy. The vacancy clusters with more vacancies can trap helium atoms more tightly. With the presence of vacancy clusters in the material, the diffusivity of helium will be significantly reduced. Moreover, the three-dimension electron density is calculated to analyze the interplay of vacancy clusters with helium. [ABSTRACT FROM AUTHOR]

Published
2018
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