Fast relaxation in a metastable metallic melt

¹ Physik-Departement, Technische Universität München - D-85747 Garching, Germany
² European Synchrotron Radiation Facility - F-38043 Grenoble, France
³ Institut für Festkörperphysik der Universität Wien - A-1090 Wien, Austria

Received: 13 February 1996
Accepted: 2 October 1996

Abstract

The recent discovery of bulk metallic glasses opened the possibility to study their metastable melt far above the glass transition temperature. Alloying to the glass ZrTiCuNiBe we succeeded in performing Mössbauer absorption experiments up to 70 K above T_g. While quasi-elastic broadening from structural relaxation was not detected, the Lamb-Mössbauer factor shows an anomalous decrease. From previous neutron spectroscopy, we exclude phonon anharmonicity as a cause. The missing elastic intensity can therefore be ascribed to a fast relaxation process. This is a first indication that the glass transition scenario predicted by mode coupling theory and observed in a number of different systems also applies to metallic alloys.