Distribution of Nb atom in the TiAl+Nb system

摘要

Based on MEAM (the modified embedded atom method) potential and an average atom model similar to BW (Bragg-Williams) method, the distribution of Nb atoms in TiAl+Nb compounds with various composition was calculated. The calculation results showed that Nb atoms prefer to occupy the Ti sublattice of Ll0, structure for all compounds in question. With increasing atomic fraction of Nb and Al, Nb atoms exhibited a trend of ordered distribution on the Ti sublattice and result in a new L10, derivatiVe superlattice structure.