New determination of the liquidus line of AuCo by magnetic measurements

Magnetic measurements of Au-Co alloys at high temperatures are presented. They prove that Au73Co27 is not the eutectic alloy but a hypereutectic one; the phase diagram is corrected and the eutectic composition is determined: 24.2 ± .2 at. % Co. Magnetic measurements of the eutectic alloy indicate the existence of small Co-clusters in the liquid state only a few degrees above the eutectic temperature.