您目前所在的位置:首页 - 期刊简介 - 详细页面

铁道科学与工程学报

JOURNAL OF RAILWAY SCIENCE AND ENGINEERING

Vol. 17    No. 2    April 2007

[PDF Download]    

    

Structural stability of intermetallic compounds of Mg-Al-Ca alloy
ZHOU Dian-wu(周惦武)1, 2, LIU Jin-shui(刘金水)3,
ZHANG Jian(张 健)3, PENG Ping(彭 平)3

1. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,
Hunan University, Changsha 410082, China;
2. School of Mechanical and Automobile Engineering, Hunan University,
Changsha 410082, China;
3. School of Materials Science and Engineering, Hunan University,
Changsha 410082, China

Abstract:A first-principles plane-wave pseudopotential method based on the density functional theory was used to investigate the energetic and electronic structures of intermetallic compounds of Mg-Al-Ca alloy, such as Al2Ca, Al4Ca and Mg2Ca. The negative formation heat, the cohesive energies and Gibbs energies of these compounds were estimated from the electronic structure calculations, and their structural stability was also analyzed. The results show that Al2Ca phase has the strongest alloying ability as well as the highest structural stability, next Al4Ca, finally Mg2Ca. After comparing the density of states of Al2Ca, Al4Ca and Mg2Ca phases, it is found that the highest structural stability of Al2Ca is attributed to an increase in the bonding electron numbers in lower energy range below Fermi level, which mainly originates from the contribution of valence electron numbers of Ca(s) and Ca(p) orbits, while the lowest structural stability of Mg2Ca is resulted from the least bonding electron numbers near Fermi level.

 

Key words: plane-wave pseudopotential theory; structural stability; electronic structure; Al2Ca; Al4Ca; Mg2Ca

ISSN 1672-7029
CN 43-1423/U

主管:中华人民共和国教育部 主办:中南大学 中国铁道学会 承办:中南大学
湘ICP备09001153号 版权所有:《铁道科学与工程学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市韶山南路22号 邮编:410075
电 话:0731-82655133,82656174   传真:0731-82655133   电子邮箱:jrse@mail.csu.edu.cn