TiO₂-BaO系融体およびTiO₂-Na₂O系融体の表面張力と密度

抄録

Surface tensions and densities of melts in the TiO₂-BaO and TiO₂-Na₂O binary systems were measured by the maximum bubble pressure method accurately. The results obtained were as follows:
(1) Surface tensions of melts in the TiO₂-BaO binary system are in agreement with calculated values from Guggenheim’s equation for ideal solution near the TiO₂-50 mol%BaO composition, but for melts in the high TiO₂ concentration region they deviate positively from calculated values for ideal solution.
While for melts in the TiO₂-Na₂O binary system they deviate negatively from the calculated values for ideal solution.
(2) Molar volumes of these two binary systems deviate positively from the additive rule on volume.
(3) Molar volumes of molten M_XO·TiO₂(X = 1 for M: Ti²⁺, Ba²⁺ and X = 2 for M: Na⁺) near the melting point increase linearly as a function of Xr_c³(r_c: the ionic radius of the cation M).
(4) Surface tensions of molten M_XO·TiO₂ near the melting point increase as the ionic potentials of the cation M increase.