Open AccessThe occupying activities of helium in ball-milled hydrogen-storage alloys
Author(s) -
Shi Liu,
Zhengli Hua,
Zhao Yue,
Xiong Liangyue,
Longbao Wang,
XinShe Yang
Publication year - 2003
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.52.756
Subject(s) - hydrogen storage , helium , materials science , ball (mathematics) , hydrogen , thermodynamics , atomic physics , alloy , composite material , physics , geometry , mathematics , quantum mechanics
Through the measurements of positron lifetime and analysis of structure, the properties of helium in the ball-milled LaNi4.75Al0.25 and Zr50Co50 alloys were investigated. It was found that the amount of the injected helium increases with increasing helium pressure. It is comparatively easier for helium to enter the LaNi4.75Al0.25 alloy. The difference of the positron lifetime parameters between the above two specimens shows that the properties of the injected helium are different. For Zr50Co50, helium occupies the intersection of two or three crystallite interfaces and/or cluster of vacancies at grain boundaries or groups of vacancies firstly. With increasing pressure of the helium atmosphere, a small amount of helium enters the free volume of single vacancies, and thus vacancy-helium compounds form. For LaNi4.75Al0.25, helium enters the free volume of single vacancies and vacancy-helium compounds form.