Thermodynamic consideration of melting of copper-based alloys with rare earths

As a fundamental study to prepare copper-based alloys with rare earths (RE: La, Gd, Nd, Cc and Y) without any inclusions, the solubility of rare earth in liquid copper was experimentally determined. Liquid copper alloys were equilibrated with carbon and rare earth carbide in a graphite crucible in an argon atmosphere at 1523-1873 K. Solubilities of rare earth in liquid copper were determined by approaching the equilibrium values from both the lower and the higher concentrations than those expected in the preliminary experiments. They were expressed as a function of temperature. Carbon in Cu-RE alloy was also analyzed and thermodynamically discussed.