Electrical conductivity measurements and electrolytic analysis of MnO-SiO₂-TiO₂ melts have been carried out in order to clarify the behavior of TiO₂ and MnO in silicate melts.
Previous studies on the electrical conductivity of Na₂O-SiO₂-TiO₂ and CaO-SiO₂-TiO₂ melts have indicated that six oxygen coordinated Ti⁴⁺ ions contribute to the electrical conductivity and that the mobility of Ti⁴⁺ ions is almost equal to that of Ca²⁺ ions.
In the present study, a similar contribution of Ti⁴⁺ ion to electrical conductivity is obtained, although the conductivity varies markedly with the MnO/SiO₂ ratio. Namely, when the ratio is small the ionic conduction result is a small value of electrical conductivity, where as when the ratio is larger than 2 the electrical conductivity rapidly increases. The increase in the electrical conductivity is considered to be due to the change from the ionic to electronic conduction. Furthermore, the mobility of Mn²⁺ ions is estimated to be nearly equal to that of Ca²⁺ ions.