Dresden 2006 – wissenschaftliches Programm

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MM: Metall- und Materialphysik

MM 21: Amorphous and Liquid Materials II

MM 21.3: Vortrag

Dienstag, 28. März 2006, 17:00–17:15, IFW D

Short-range Order in Undercooled Ti-Fe-Si-O Melts — •Oliver Heinen, Dirk Holland-Moritz, and Dieter M. Herlach — DLR, Inst. für Raumsimulation, D-51170 Köln

Comparing the energy of different types of monoatomic clusters and assuming radial symmetric Mie type interaction potentials, the icosahedron truns out to be the most stable configuration of all clusters with 13 atoms. Basing on this finding Frank proposed an icosahedral short-range order (SRO) prevailing in metallic liquids. This hypothesis has been approved by a number of experimental and theoretical examinations. The assumption of radial symmetric interaction potenials is justified for purely metallic systems. In this work we present investigations of the SRO of liquids containing metallic as well as covalent bonding atoms. For the investigation the Ti-Fe-Si-O system was chosen since this system is supposed to have strong covalent Ti-O bonds in the solid as well as in the liquid state. The liquids were containerlessly processed and in-situ investigated using the combination of the electromagnetic levitation technique together with energy dispersive diffraction of synchrotron radion at the European Synchrotron Radiation Facility as well as neutron diffraction at the Institute Laue-Langevin. This work was financially supported by DFG under contract No. Ho1942/4 and by ESRF and ILL.