Partial structure factors of liquid al80 (mnx(fecr) 1-x)20 alloys

Abstract

The structure of the liquid Al 80 (Mn x (FeCr) 1-x ) 20 alloys has been studied using neutron diffraction and the substitution between Mn atoms and the σ-FeCr mixture. We have checked that this subtitution is isomorphous by performing four measurements on different mixtures with x=1, 0.639, 0.304 and 0. The Bhatia-Thornton as well as the Faber-Ziman partial structure factors have been determined and in particular, certain features in the S NN function and in the distribution of transition metal atom pairs point out to the existence of a well-defined topological ordering. But a simple comparison between the interatomic distances and partial coordination numbers in the liquid, quasicrystalline and crystalline phases is still insufficient to characterize clearly the type of local order. The chemical ordering effects in these liquid alloys are relatively moderate with a chemical short-range order parameter of 0.05 Etude par diffraction de neutrons de la structure des alliages liquides Al 80 (Mn x (FeCr) 1-x ) 20 . On verifie que la substitution entre les atomes de Mn et le melange FeCr-σ est isomorphe en realisant des experiences sur des melanges differents tels que x=1; 0,639; 0,304, et 0. Determination des facteurs de structure partiels de Bhatia-Thornton et de Faber-Ziman