title: Study of amorphous alloy structures with medium range atomic ordering.
abstract: Structures with atomic medium range order (MRO) extending as small as approximately 2 nm in amorphous alloys can be observed under suitable defocus conditions as clear lattice fringe images by means of axial-beam high-resolution electron microscopy (HREM). In this article, our studies of local structure observation in some metal-metalloid amorphous alloys with the "selected-defocus method" are introduced. Also introduced are an HREM image simulation study of amorphous alloy structures and a nano-probe (1-1.5 nm) electron diffraction analysis of MRO structure. A multislice image simulation study for suitable structure models (1) with a random atomic distribution, (2) with MRO regions having different sizes, distributions, and specimen thicknesses, is a necessary step to verify the MRO observation in amorphous alloys. It was demonstrated that not only HREM information but also nano-diffraction information are necessary in order to understand local structures of amorphous alloys.
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hirotsu
authors.forename: T
authors.initials: T
authors.lastname: Ohkubo
authors.forename: M
authors.initials: M
authors.lastname: Matsushita
mesh_terms: D000497:Alloys / Q000737:chemistry*; D003460:Crystallization; D007501:Iron / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008854:Microscopy, Electron; D008958:Models, Molecular; D010165:Palladium / Q000737:chemistry; D012825:Silicon / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000497:Alloys; D008670:Metals; D010165:Palladium; D007501:Iron; D012825:Silicon