Synchrotron x-ray total scattering and modeling study of high-pressure-induced inhomogeneous atom reconfiguration in an equiatomic Zr50 Cu50 metallic glassy alloy

DOI: 10.1103/PhysRevB.105.064203

Authors: Shifeng Luo (Hefei University of Technology; University of Hull; Northwestern Polytechnical University) , Jia Chuan Khong (University of Hull; Northwestern Polytechnical University) , Dominik Daisenberger (Diamond Light Source) , Shi Huang (University of Hull) , Paul F. Mcmillan (University College London) , Jiawei Mi (University of Hull; Shanghai Jiao Tong University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B , VOL 105

State: Published (Approved)
Published: February 2022
Diamond Proposal Number(s): 8858 , 9902

Abstract: We studied in situ the local atomic structure evolution of an equiatomic Zr 50 Cu 50 metallic glassy alloy under high pressure compression inside a diamond anvil cell using synchrotron x-ray total scattering. The empirical potential structure refinement method was used to reconstruct the three-dimensional atomic models at each pressure step, and to analyze the spatially averaged local atomic structure configurations. The interatomic distances of different atomic pairs are reduced at different rates with increasing pressure and the Cu-Cu pairs exhibit the highest percentage reduction. Between ambient pressure and 36.85 GPa, the atomic separation of the Cu-Cu pairs is reduced by ∼12% compared to ∼5% for Zr-Zr and Zr-Cu pairs. Such disproportional decrease in interatomic distance results in inhomogeneous atom reconfiguration in the short atomic range. With the increase of pressure, the Zr atoms move preferentially towards the Zr-Zr pairs, while the Cu atoms move preferentially towards the Cu-Cu pairs, creating inhomogeneous atom reconfiguration with positive short-range order coefficients of 0.0309 and 0.0464 for Zr-Zr and Cu-Cu respectively, but a negative value of −0.0464 for Zr-Cu pairs. Voronoi tessellation method was also used to study the evolution of the short-range atom packing versus pressure, elucidating the cause for the bimodal distribution of the bond angle distributions. The research sheds light on understanding of the atomic reconfiguration of equiatomic alloys under high pressure.

Journal Keywords: Atomic & molecular structure; Interatomic & molecular potentials; Pressure effects; Metallic glasses; X-ray scattering

Diamond Keywords: Alloys

Subject Areas: Materials, Engineering


Instruments: I15-Extreme Conditions

Added On: 15/02/2022 09:00

Discipline Tags:

Materials Engineering & Processes Materials Science Engineering & Technology Metallurgy

Technical Tags:

Scattering Total Scattering