Structure analysis of amorphous alloys by modern electron diffraction techniques

Abstract We have developed a structure analysis method for a comprehensive understanding of average and local structures of amorphous alloys by taking advantage of modern electron diffraction techniques. Structural details are analyzed in amorphous thin-film and ribbon specimens with compositions near Pd 75 Si 25 . Selected area electron diffraction (SAED) and nanoprobe electron diffraction patterns were taken by using the imaging-plate technique to measure diffraction intensities for the average and local structure analyses. According to the analyses of nano-diffraction patterns with various zone-axes from atomic medium range order (MRO) regions, MRO structures in both of the alloy specimens are of hexagonal Pd 2 Si-type but with slightly different lattice parameters. By comparing the atomic pair distribution function data from the SAED intensity analyses and the structural data from the nano-diffraction pattern analyses, it has been demonstrated that not only a local atomic structural change, but also an atomic density fluctuation occurs via MRO formation in both of these amorphous alloys.