| Calciothermic reduction of Nd₂O₃ was attempted to produce Nd-Fe mother alloy in the presence of a flux, CaCl₂ at temperatures of 820℃ to 1050℃. Feed material was a powder mixture of Nd₂O₃, Ca, CaCl₂ and Fe, having a given composition. Reduction experiments were carried out under stirring condition and reduced Nd was collected into a molten metal pool of Nd-Fe alloy at the bottom of the crucible. Recovery of the metallic Nd was calculated by the difference of weights of the alloy and slag. Alloy and slag thus made were analyzed by I.C.P., SEM and X-ray diffractometer. Metal recovery was increased with increasing temperature, reaction time and also stirring rate. Experimental results showed that the optimum amounts of metallic Ca and CaCl₂ were 15% in excess than the theoretical amount and 4.0 mole ratio to the theoretical moles of CaO formed, respectively. The alloy composition was in the range of 76.31 to 85.23wt% Nd, 13.90 to 23.41wt% Fe and 0.29 to 0.39wt% Ca depending on the experimental temperature. The best purity of the alloy was analyzed to be 99.55wt%. |
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