1988 年 29 巻 12 号 p. 990-1002
The densities of melts in the system FeO–FeO2O3–BaO and BaO–BaCO3 have been measured under controlled atmospheres from the liquidus temperature to 1873 K by using the Archimedean method. The molar volumes of melts in the binary system BaO–BaCO3 satisfy the additive rule. On the other hand, the molar volumes of melts in the ternary system FeO–Fe2O3–BaO show a possitive deviation from the additive rule and can be reproduced to within ±0.6% by the following equations:
VM(cm3⁄mol)=15.54NFeO+37.16NFe2O3+31.27NBao+3.05NFe2O3NBao⁄(NFe2O3+NBao) at 1673 K,
=15.66NFeO+37.50NFe2O3+31.40NBaO+2.98NFe2O3NBaO⁄(NFe2O3+NBaO) at 1773 K,
=15.80NFeO+37.84NFe2O3+31.53NBaO+2.91NFe2O3NBaO⁄(NFe2O3+NBaO) at 1873 K,
A similar positive deviation is not observed for the melts in the system FeO–Fe2O3–CaO. This suggests that the addition of Ba2+ cation results in the polymerization of ferrite anions as FeO45−.