Reassessment of the Ce-Ni binary system supported by key experiments and ab initio calculations

The Ce-Ni system is reassessed by means of CALPHAD (CALculation of PHAse Diagram) approach, supplemented with decisive experiments and enthalpies of formation computed via VASP (Vienna ab initio simulation package) code. Fourteen alloys are prepared in order to check the general feature of the established Ce-Ni phase diagram and to provide new phase diagram data for the refinement of previous modeling. The phase identification for both as-cast and annealed states is performed by means of X-ray diffraction technique, and the phase transition temperatures are measured by differential thermal analysis. Electron probe microanalysis is employed to determine two tie lines between CeNi5 and (Ni). The enthalpies of formation for CeNi2 and CeNi5 are calculated using VASP code with a desire to clarify the discrepancies among the literature data. A set of self-consistent thermodynamic parameters for the Ce-Ni system are finally obtained. Significant improvements have been made, compared with the previous assessments. (c) 2007 Elsevier Ltd. All rights reserved.