Open AccessElectron-theoretical study of grain refining mechanism of Mg alloys
Author(s) -
Guili Liu
Publication year - 2009
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.58.3319
Subject(s) - materials science , atom (system on chip) , nucleation , binding energy , impurity , refining (metallurgy) , surface energy , atomic physics , chemical physics , electron , thermodynamics , metallurgy , chemistry , physics , organic chemistry , computer science , composite material , embedded system , quantum mechanics
The electronic parameterssuch as the structural energy and atom binding energy of both α-Mg and α-Zrthe Mg/Zr interface energy and surface energy of Mgas well as the interaction energies between Zr atoms and between Zr and impurity atomswere calculated by means of recursion method. The calculated results showed that the structural energy and atom binding energy of α-Zr are lower than those of α-Mgand the Mg/Zr interface energy is lower than the surface energy of Mgwhichin an energetical pointexplains the experimental phenomenon. SpecificallyZr particles first crystallize out of the Mg liquid and then act as heterogeneous nucleation sites to refine the Mg grains. The atom interaction energies indicate that the Zr atoms can attract each other to form Zr atom clusters in Mgand combine with impurity atoms to form compoundsthus weakening the Mg grain refining effect.