Structural observation and RMC modeling for Ni-Zr and Cu-Zr metallic glasses

Ni-Zr and Cu-Zr metallic glasses were employed to elucidate characteristics of shortand medium-range structure by neutron diffraction. The pre-peak characteristic of the mediumrange order was clearly observed at Q∼17 nm ^-1 in the structure factor, S(Q), for the Ni_33.3Zr _66.7 metallic glass. The reverse Monte Carlo (RMC) modeling was also carried out for elucidating the characteristics of the structure for the Ni ₃₃₃Zr₆₆₇ and Cu_33.3Zr_66.7 metallic glasses. The characteristic Ni-Ni partial structure factor obtained experimentally was definitely reproduced by the RMC modeling. Moreover, it was found that the first neighbor distributions of the Ni-Ni and Ni-Zr pairs for the Ni_33.3Zr_66.7 metallic glass were much sharper than those of the Cu-Cu and Cu-Zr pairs for the Cu_33.3Zr_66.7 metallic glass. The evidence is strongly correlated with the short- and medium-range order of the structure for metallic glasses.