Electrical
Conductivity of Molten TbCl3-Tb Mixtures
O. Tkatcheva, A. Red'kin, V. Shishkin, and V. Khokhlov
Institute of High-Temperature Electrochemistry
20 S. Kovalevskaya Str., 620219 Ekatherinburg, Russia
The electrical conductivity of TbCl3-Tb melts has been measured depending on temperature and metal concentration. The Tb solutions in trichloride terbium containing from 0 to 10 at.% of metal were studied in temperature range from 820 to 1180 K. The experimental measuring device used was described earlier [1].
It was found that the specific conductivity (k) of molten TbCl3-Tb mixtures containing up to 5.5 at.% Tb rises with increasing temperature by the linear equation: k = k0 + (dk/dT)T, whereas that of more concentrated solutions grows exponentially with elevating temperature. The polytherms of the electrical conductivity of melts under study are shown in Fig.1. It can see from data presented that there are the points of inflection in the curves, which account for the liquation temperatures.
Fig. 1. Electrical conductivity of molten Fig. 2. Electrical conductivity of molten
TbCl3-Tb mixtures against temperature TbCl3-Tb mixtures as a function of metal
concentration
As illustrated in Fig.2, the concentration dependence of the electrical conductivity leads us to conclude that the solubility of rare earth metal included in the yttrium group in its trichloride is less than that of cerium group metal. Moreover, for terbium solutions the increasing conductivity related to the specific conductivity of molten salt-solvent is much below that for cerium solutions at the same metal concentration and temperature [1].
The observed regularities are discussed in terms of advanced view of ion-electronic melts containing different valence ions of rare earth metals.
1. A.Red’kin, O.Tkatcheva, V.Shishkin, V.Khokhlov. Electrical Conductivity of Molten System KCl-CeCl3-Ce. – High Temperature Material Processes, 1998, Vol. 2, No.4, p.p. 581-586.