The atomic cluster model of α phase of ZA27 high angle grain boundary including rare earth elements (La, Y) and η phase was constructed by self-developed computer programm. Recursion method was used to calculate the local density of states of Al, Zn, La and Y elements, and the total density of states and Fermi level of α phase and η phase. The influence of rare earth elements (La, Y) on the density of states and Fermi level was discussed. The calculated results show that: the local density of states of RE element are similar to that of Zn, so RE element can combine with Zn easily; RE element can reduce the Fermi level of η phase, lower the difference of electrode-potential between Zn and Al, so RE element is of the function to restrain the intergranular corrosion of zinc-aluminum alloys; RE element can not change the shape of total density of state of α and η phase, but can heighten the total density of state of η phase, and change the electronic structure of η phase; the crystal structure have effect on the atomic density of states, the density of state of impurity atom go tends to be similar with that of matrix atom.

Key words: rare earth, grain boundary, intergranular corrosion, electronic structure