Structure of liquid Al-Ge-Ni melts in a wide composition range

Abstract

X-ray diffraction study of the Al-Ge-Ni melts along different sections of the ternary phase diagram has been discussed. The measurements were taken at 1000 °C or at temperatures on 50° above liquidus for compositions with high melting point. It has been shown that AlNi interactions play the most important role in the formation of the local atomic structure in the Al-Ge-Ni melts. The most significant decreasing of the nearest interatomic distance (R1) takes places with addition of Ni to binary AlGe alloys. There is a competition between Al and Ge atoms in the formation of local atomic structure around Ni atoms. For ternary melts with high Ge content the influence of GeGe pairs increases resulting in the formation of the clusters with structure similar to the liquid germanium. The ribbons of the Al79Ge15Ni6, Al61Ge29Ni10 and Al61Ge15Ni24 alloys have been obtained by rapid solidification from the liquid state. The phase analysis of the as-quenched and annealed ribbons has been discussed.