Structural study of quasicrystallization in Zr–NM (NM=Pd or Pt) metallic glasses

Abstract Glassy Zr 70 Pd 30 and Zr 80 Pt 20 alloys were prepared by melt spinning. Icosahedral-like local atomic configurations were identified in these alloys by ordinary and anomalous X-ray scattering measurements. In the case of Zr 70 Pd 30 alloy, the total coordination numbers ( N ) around Zr and Pd in the nearest neighboring region were 11.3 and 8.9, respectively, which implies the existence of an icosahedral-like local atomic structure around Zr. On the other hand, the glassy Zr 80 Pt 20 alloy shows a pronounced pre-peak in its X-ray scattering intensity profile, indicating strong chemical short-range-ordered clusters. The N values around Zr and Pt are both 11.1, and close to 12.0. Furthermore, the atomic distances of Zr–Zr and Pt–Pt are almost the same. Thus, icosahedral-like local atomic structures with strong correlations are already formed both around Zr and Pt. The stronger chemical affinity of the Zr–Pt pair over the Zr–Pd pair seems to contribute to the stabilization of the quasicrystalline phase through the rigid icosahedral clusters.