[en] The elastic properties of the isotropic state of condensed matter are given by the elastic constants ell and c44. In the liquid state the static shear stiffness c44 vanishes whereas at sufficient high probe frequencies a dynamic shear stiffness may appear. In that latter case the question about the existence of a Cauchy relation appears. It will be shown that a pure Cauchy relation can appear only under special conditions which are rarely fulfilled. For all investigated materials, including ceramics, liquids and glasses, a linear relation between ell and c44 called generalized Cauchy relation is observed, which, surprisingly, follows a linear transformation.
Disciplines :
Physics Materials science & engineering
Identifiers :
UNILU:UL-ARTICLE-2009-032
Author, co-author :
Bactavatchalou, R.; Laboratoire Européen de Recherche Universitaire Saarland-Lorraine-Luxembourg at Universität des Saarlandes
Alnot, Patrick; Université Henri Poincaré, Nancy I.
BALLER, Jörg ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
Kolle, M.
Müller, Ulrich ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
SANCTUARY, Roland ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
Tschöpe, A.
Vergnat, Ch
Wetzel, Berndt; Institut für Verbundwerkstoffe TU Kaiserslautern 67663 Kaiserslautern
KRÜGER, Jan-Kristian ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit