| 摘要 |
PURPOSE:To prevent a magnetic alloy from being oxdized during treatments thereof, by applying a metallic alcoholate on a permanent magnet formed by molding and sintering a R2T14B permanent magnet material and hydrolyzing the metallic alcoholate to form a coat of a metal oxide on the surface of the permanent magnet. CONSTITUTION:Nb having a purity of 95% or over, electrolytic iron and crystal born are melted and cooled in the atmosphere of argon to obtain an ingot. The ingot is then ground and molded under pressure. The pressure-molded powder body is sintered and cooled slowly. The body is further heated and quenched to obtain a permanent magnet. The permanent magnet thus obtained is degreased with trichloroethylene, and Si alcoholate is applied thereon by spraying the same. The permanent magnet is then heated for 20min at a temperature of 100-200 deg.C. In this manner, a transparent SiO2 film can be formed on the surface of the magnet. |
