Dresden 2003 – wissenschaftliches Programm
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M: Metallphysik
M 2: Symposium: Phasenumwandlungen in Schmelzen I
M 2.1: Vortrag
Montag, 24. März 2003, 10:15–10:30, IFW A
Temperature Dependence of the Short-Range Order in Stable and Undercooled Metallic Melts — •Dirk Holland-Moritz1, Thomas Schenk1, Dieter M. Herlach1, Virginie Simonet2, and Robert Bellissent3 — 1DLR, Institut für Raumsimulation, D-51170 Köln — 2Laboratoire Louis Néel, CNRS, BP 166, F-38054 Grenoble Cedex, France — 3Centre d’Etudes Nucleaires de Grenoble, DRFMC / SPSMS / MDN, F-38054 Grenoble Cedex, France
This work presents investigations on the short-range order of stable and deeply undercooled liquids of the pure elements Ni, Co, Zr and Fe and alloys forming polytetrahedral phases (Al13(Fe,Co)4) as a function of the temperature. The liquids were containerlessly processed und undercooled by utilization of the electromagnetic levitation technique which was combined with techniques of elastic neutron scattering and energy dispersive diffraction of synchrotron radiation in order to determine the structure factors of the liquids. The experimentally determined structure factors were simulated by assuming different types of short-range order prevailing in the liquid. The best fit of the experimental data is obtained if an icosahedral short-range order is assumed, independently on the structure of the corresponding solid phase. This short-range order gets more pronounced if the temperature is decreased.
This work was supported by DFG under contract Nos. Ho1942/1 and Ho1942/2.