Local Atomic Structures in Amorphous and Quasicrystalline Zr70Ni10Pt20and Zr80Pt20Alloys by the Anomalous X-ray Scattering Method
AbstractLocal atomic structures around Zr and Pt in a quasicrystalline Zr80Pt20alloy, and amorphous and quasicrystalline Zr70Ni10Pt20alloys have been determined by the anomalous x-ray scattering (AXS) method. A distinct prepeak observed in an intensity profile of the amorphous Zr70Ni10Pt20alloy indicates existence of strong chemical short-range order (CSRO) clusters in the amorphous phase. Total coordination numbers around Zr and Pt in a nearest neighbor region in both alloys have been evaluated. The values around Pt are almost equal to 12 in the amorphous and quasicrystalline states suggest formation of icosahedral clusters around Pt. Some of crystalline structures formed from the quasicrystalline phases by annealing consist of icosahedral clusters of Zr and Ni atoms, or polyhedral clusters of Zr and Pt atoms similar with icosahedral clusters. The present result appears to support that the phase transformation from the amorphous to the crystal through the quasicrystal is explained by the icosahedral CSRO clusters in the amorphous and quasicrystalline states.
Local Atomic Structures of Zr70Ga10Ni20 Amorphous Alloys by the Anomalous X-ray Scattering Method
