THE SPECIFIC-HEAT OF HIGHLY UNDERCOOLED (CO, NI, FE)-PD MELTS

The systematic measurements of the specific heat of the completely mis cible metallic systems (Go, Ni, Fe)(x)Pd-100-x in the liquid and cryst alline state are reported. These systems offer undercooling ranges of about 350 K below their respective liquidus temperatures by applying t he melt fluxing technique. In the case of Co-Pd, measurements of the s pecific heat of the undercooled liquid could be extended down into the very vicinity of the Curie temperature of the crystalline phase. Appr oaching this temperature regime, the specific heat shows a measurable increase. For hii-Pd and Fe-Pd systems, the Curie temperatures are far below the melting temperatures. The specific heat for these systems i n the liquid state is almost independent of temperature, although the same amount of undercooling was achieved. These results, together with recent measurements of the magnetization of undercooled Co-Pd alloys, indicate the onset of an ordering transition - probably due to magnet ic interaction - in the undercooled state of Co-Pd.