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  • Structural evolution in Au- and Pd-based metallic glass forming liquids and the case for improved molecular dynamics force fields
Title: Structural evolution in Au- and Pd-based metallic glass forming liquids and the case for improved molecular dynamics force fields
The results of a combined experimental and computational investigation of the structural evolution of Au 81 Si 19 , Pd 82 Si 18 , and Pd 77 Cu 6 Si 17 metallic glass forming liquids are presented. Electrostatically levitated metallic liquids are prepared, and synchrotron x-ray scattering studies are combined with embedded atom method molecular dynamics simulations to probe the distribution of relevant structural units. Metal–metalloid based metallic glass forming systems are an extremely important class of materials with varied glass forming ability and mechanical processibility. High quality experimental x-ray scattering data are in poor agreement with the data from the molecular dynamics simulations, demonstrating the need for improved interatomic potentials. The first peak in the x-ray static structure factor in Pd 77 Cu 6 Si 17 displays evidence for a Curie–Weiss type behavior but also a peak in the effective Curie temperature. A proposed order parameter distinguishing glass forming ability, [Formula: see text], shows a peak in the effective Curie temperature near a crossover temperature established by the behavior of the viscosity, T A .  more » « less
Award ID(s):
1904281
PAR ID:
10425126
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
19
ISSN:
0021-9606
Page Range / eLocation ID:
194501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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