Effect of pre-irradiation defects on helium trapping and diffusion in RAFM steel

Nuclear Fushion

article

Xiuxuan Duan¹  Shuoxue Jin¹  Yamin Song¹  Yanli Wang²  Yi Xiong⁴  Weiping Zhang⁵  Shilei Li²  Xingzhong Cao¹ 

[1] Multi-disciplinary Research Division, Institute of High Energy Physics, Chinese Academy of Sciences;State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing;University of Chinese Academy of Sciences;Science and Technology Institute, Laboratory for Electron Microscopy, Wuhan Textile University, Wuhan Textile University;School of Mathematics and Physics, Hebei University of Engineering

关键词: He-vacancy complex;    pre-irradiation defect;    positron annihilation;    RAFM steel;   

DOI  :  10.1088/1741-4326/acadf2

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

In order to analyze the effect of pre-irradiation defects on helium trapping and diffusion behaviors in detail by slow positron beam, Si ion with high energies (300 keV and 6 MeV) and 100 eV helium plasma were sequentially introduced into reduced activation ferritic/martensitic steel. Massive microscopic defects were observed in Si ion irradiated specimens. Low energy helium (∼100 eV) atoms could diffuse into much deeper region in metals without displacement damage. In the diffusion process of helium atoms, they would be trapped by the Si-ion pre-irradiation defects. The formation of He-vacancy complexes would affect the annihilation of positrons with the electrons in pre-irradiation defects and decrease theSparameters. The shallow region defects induced by 300 keV irradiation have more obvious advantage of hindering the diffusion of helium over the deep defects than that in 6 MeV irradiation. Thus, the pre-introduced defects can trap effectively helium atoms and hinder their diffusion.

【 授权许可】

Unknown