Atomic structure of nanoscale quasicrystal-forming Zr-noble metal binary metallic glasses

作者：Saida J^*; Itoh K; Sanada T; Sato S; Imafuku M; Ohnuma M; Inoue A

来源：Journal of Alloys and Compounds, 2011, 509: S27-S33.

DOI：10.1016/j.jallcom.2010.12.076

• Metallic glasses
• Quasicrystallization
• Local structure
• Simulation
• Zirconium-based alloy

We report the results of the local structural evaluation and mechanism of QC formation in the Zr(70)Pd(30) and Zr(80)Pt(20) glassy alloys. Voronoi analysis indicates the difference of local environment between two alloys. The perfect icosahedron frequently exists around Zr atom and major polyhedra have prism-like structure around Pd in Zr(70)Pd(30). In contrast, icosahedral-like distorted polyhedra formation is favorable around Pt as well as Zr in Zr(80)Pt(20). It is therefore, concluded that the quasicrystallization originates from the medium-range order based on the Zr-centered perfect icosahedron and the Pd-centered prism-like ones remain during the QC phase formation in Zr(70)Pd(30). Icosahedral-like local structure around Zr and Pt might contribute together to the nucleation of QC phase in Zr(80)Pt(20). This feature with a different mechanism of QC formation in the two alloys may correlate to the difference of solute concentration and the structure of stable crystalline phase after the decomposition of QC phase.

• 出版日期2011-6