Abstract
By employing quasielastic neutron scattering, we studied the atomic-scale relaxation dynamics and transport mechanism of La50Ni15Al35 and Ce70Cu19Al11 metallic glass melts in the temperature range of >200K above their liquidus temperatures. The results show that both liquids exhibit stretched exponential relaxation and Arrhenius-type temperature dependence of the effective diffusion coefficient. The La50Ni15Al35 melt exhibits an activation energy of 0.545 ± 0.008 eV and a stretching exponent ∼0.77 to 0.86 in the studied temperature range; no change of activation energy, as suggested in previous reports, associated with liquid-liquid phase transition was observed. In contrast, the Ce70Cu19Al11 melt exhibits larger diffusivity with a much smaller activation energy of 0.201±0.003eV and a smaller stretching exponent ∼0.51 to 0.60, suggestive of more heterogeneous dynamics.
Original language | English |
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Journal | Physical Review B |
Volume | 103 |
Issue number | 22 |
DOIs | |
State | Published - Jun 1 2021 |
Funding
This paper is supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Award No. DE-SC0014084. This paper used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.