Reversible atomic processes as basic mechanisms of the glass transition

*Institut für Theoretische und Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany;
^†State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083, People's Republic of China;
^§Institut für Materialphysik, Technische Universität Graz, Petersgasse 16, A-8010 Graz, Austria;
^¶Materials Division, Universität Ulm, Albert-Einstein-Allee 47, 89081 Ulm, Germany; and
^‖Institut für Nanotechnologie, Forschungszentrum Karlsruhe, 76021 Karlsruhe, Germany

Communicated by Manuel Cardona, Max Planck Institute for Solid State Research, Stuttgart, Germany, June 7, 2007 (received for review April 4, 2007)

Abstract

Reversible formation and disappearance of vacant spaces (vacancy-type defects) in bulk Zr₅₇Cu_15.4Ni_12.6Nb₅Al₁₀ glass are directly evidenced by high-resolution, time-differential dilatometry studies. The vacancy kinetics are strongly temperature-dependent, with an effective migration enthalpy of H _V ^M = 3.34 eV. This may explain the strong temperature dependence of glass properties such as viscosity. The results presented here are of general importance for understanding amorphous condensed matter and biomaterials and for the technical development of amorphous steels.

Footnotes

^‡To whom correspondence should be addressed. E-mail: yefeng{at}skl.ustb.edu.cn
Author contributions: F.Y. and H.-E.S. designed research; F.Y., W.S., and R.K.W. performed research; F.Y., W.S., and H.-E.S. analyzed data; and F.Y., H.-J.F., and H.-E.S. wrote the paper.
The authors declare no conflict of interest.
Abbreviation:

BMG,

bulk metallic glass.