Abstract
The author and Mr. Kumahiko Hasegawa have described on the relation between the natural and artificial iron oxides which were reduced with H2, CO, and coal gases, and their magnetic properties. It is also discussed that the magnetic properties of the reduced iron oxide heated in air and vacuum are variable.
The present paper follows the previous one, and the following items are described as the many experimental results.
1. Measurement of permeability by ballistic galvanometer.
2. The permeabilities of Fe3O4 and FeO.
3. The relation between the permeability of iron oxide and field intensity.
4. The relations between vacuum heating of the natural and reduced iron oxides, and their permeabilities.
5. The relations between the FeO contents of the natural and reduced iron oxides, and their permeabilities.
6. The state of combination of iron with oxygen and solid solution between iron oxides.
The maghetic permeabilities of Fe3O4 and FeO are determmed as 6.27 and 2.43 respectively.
After vacuum heating of the samples at above 600°C, though chemical compositions of the iron oxides do not alter, their permeabilities show the remarkable increase, and the relations between the permeabilities of the reduced iron oxides and the field intensities approach gradually to those of natural magnetic oxide.
Then by the vacuum heatings of reduced and natural iron oxides, there are interesting tendencies between the Feo contents and permeabilities. Any sample approaches gradually to the theoretical combined state of FeO and Fe2O3, namely Fe3O4, after the treatments.
Estimating the combined states of oxygen from the above relation, the natural and reduced iron oxides consist partly of the cubic form of Fe3O4, and partly of Fe2O3+Fe3O4, Fe3O4+Fe2O3, Fe3O4+FeO, FeO+Fe3O4, and FeO+Fe at the state of solid solution, and FeO in free state.
By vacuum heating of iron oxide, the cubic form of Fe3O4 are disintegrated from these solid solutions and their permeabilities are increased.
