| 摘要 |
PURPOSE:To sufficiently improve magnetic characteristics and durability and to sufficiently improve the magnetic characteristic, electromagnetic conversion characteristic and durability of a magnetic recording medium obtained by using ferromagnetic metal powder containing iron as a main ingredient by incorporat ing aluminum, silicon and phosphorus in the powder containing as the main ingredient the iron. CONSTITUTION:Ferromagnetic metal powder containing as a main ingredient contains aluminium, silicon and phosphorus. In this instance, 0.2-15.0wt.% of aluminium, 0.05-15.0wt.% of silicon and 0.05-5.5wt.% of phosphorus are contained based on the iron, and it is preferable that more aluminium, silicon and phosphorus are present on the surface of the powder particles. Further, the surfaces of oxyhydroxide particles of oxide particles containing as a main ingredient iron are treated with aluminum compound, silicon compound and phosphorus compound to be covered therewith, then thermally reduced in a reducing gas atmosphere to incorporate aluminium, silicon and phosphorus in the particles, thereby manufacturing the ferromagnetic metal powder. |
