Atomic packing and short-to-medium range order evolution of Zr-Pd metallic glass

Abstract

A larger-scale Zr 70 Pd 30 alloy system has been simulated using molecular dynamics (MD) to investigate structure evolution in Zr 70 Pd 30 . In the Zr-Pd binary system, the nature of the amorphous-to-quasicrystalline phase transition has been clarified [4,5]. However, the characteristic structure in the Zr 70 Pd 30 MGs is currently unknown. We also do not know whether the structures of Zr 70 Pd 30 MGs directly affect the transition into the quasicrystalline phase. In the present study, the transition of the Zr 70 Pd 30 alloy from the supercooled liquid to the solid is simulated using molecular-dynamics (MD). The structure of the Zr 70 Pd 30 metallic glass is investigated in detail by means of the pair distribution function (PDF), pair analysis method (PA) [6,7] and Voronoi polyhedron analysis method. Based on the hypothesis that linking icosahedra can form the quasicrystalline phase, there has been considerable interest in the icosahedral medium range ordering (IMRO) of , which probably affects the glass formability as well as the mechanical properties, including Young's modulus and shear banding resistance [14]. Recently, some models for IMRO in MGs have been suggested by experimental and computational studies [15][16][17][18][19][20][21][22].

Design and Characterisation of Metallic Glassy Alloys of High Neutron Shielding Capability

“…The pair distribution function (PDF) derived based on the diffraction dataset is an ideal technique to study the short (<5 Å) and medium (5 Å~20 Å) range atomic structures24, especially for metallic glasses25. While long atomic range often refers an atomic distance of >20 Å26.…”