EXAFS studies on glass-forming ability of amorphous Mg₆₅Cu₂₅Y_xGd_10-x (x=0, 5, 10) alloys

Local atomic structures of amorphous Mg₆₅Cu₂₅Y_xGd_10-x (x=0, 5, 10) alloys and the difference in glass-forming ability of them have been studied by extended X-ray absorption fine structure (EXAFS). Results showed that the coordination number around Cu atoms in amorphous Mg₆₅Cu₂₅Y_xGd_10-x alloys increased monotonously while the distance between Cu atoms and their nearest neighbor atoms decreased slightly with the increase of element Gd content, indicating the short range order around the Cu atoms improved. The formation of polyhedral short-range order unit with more coordination number and stronger binding around Cu atoms in Mg₆₅Cu₂₅Y_xGd_10-x alloys was in favor of the improvement of glass-forming ability.