Manufacture of stable ferromagnetic metallic powder

Abstract

Abstract PURPOSE:To manufacture stably ferromagnetic metallic powder with especially high coercive force and high saturation magnetizability in a fine-grained state by reducing a starting material contg. acicular iron oxyhydroxide or ferric oxide as the principal component with a reducing gas, and immersing the resulting magnetic metallic powder in an aqueous soln. of a corrosion controller. CONSTITUTION:Said magnetic metallic powder, that is, fine acicular powder of iron or Fe-Co-Ni is immersed in an aqueous soln. contg. a corrosion controller by 5-1,000wt% of the amount of the powder. The temp. of the soln. is <=50 deg.C, practically 10-50 deg.C. Nitrite, boric acid, borate, silicate, phosphate or the like is used as the corrosion controller. For example, when an aqueous soln. of NaNO2 is used, the concn. is preferably adjusted to 25-100%.

Inventors

• 👤 Kazunobu Tomimori
• 👤 富盛　和宣
• 👤 Takeshi Tobisawa
• 👤 飛沢　猛
• 👤 Katsuhiko Kawakami
• 👤 河上　克彦

Bibliographic Details