Abstract
By heating under water vapor, ferrite was formed from coprecipitate made from constituent sulfate solution or wet mixture of component hydroxides, similar to the case of hydrothermal synthesis. Temperature (100°C-300°C) had a marked effect on the velocity of the formation.
In the case of Ni ferrite, pressure of water vapor played an important role on the formation, while in the case of Zn ferrite, it appears that only a small amount of water vapor was enough for the formation.
Even from the dry mixture of component hydroxides, ferrite of normal structure was formed. The formation by this process from the coprecipitate or wet mixture heated in air up to 250°C was also evident.
From these results, some discussions were made on the mechanism of the formation.
