| 摘要 |
PURPOSE:To prepare a metal-Co magnetic powder having a good configuration and high saturation susceptibility, by reducing a metal compound powder containing Co as a main component under heating in a reductive atmosphere in such a state that the particle surface of said powder is coated with an Si-compound. CONSTITUTION:A water-soluble silicate is dissolved in an aqueous alkali solution and, after a metal compound powder containing Co as a main component is dispersed in said aqueous solution, CO2 gas is blown thereinto or an acid is added thereto to neutralize said solution while precipitating a silicate sol to the surface of each particle. In the next step, the sol coated powder particles are separated and washed and, after drying, the obtained particles are subjected to heat treatment at about 200-1,000 deg.C while the treated particles are reduced under heating in a reductive atmosphere to prepare a metal-Co magnetic powder. By this method, because the shape of the particles are effectively held and the sintering between the particles are effectively suppressed, heating reduction is performed sufficiently well and a uniform well-shaped particulate or plate shaped metal-Co magnetic powder having high magnetic saturation susceptibility is obtained. |
