| 摘要 |
PURPOSE:To form a strong corrosion resisting film on a surface without deteriorating the magnetic properties of an Fe-Al soft magnetic material, as a material to be treated, at the time of magnetic annealing. CONSTITUTION:Plural materials 1 to be treated, composed of Fe-1%Al soft magnetic materials, are heated and held in a reducing atmosphere at 950-1150 deg.C for prescribed time and cooled slowly, together with a heat treatment jig 2 constituted of a sintered compact of A;2O3. The arrangement jig 2 is constituted of a supporting body 3 for arranging the materials to be treated into laminated state and supporting them, a base 4 for holding the supporting bodies, and a cover 5. Al constituting the jig is allowed to diffuse into the surface layer part of the materials to be treated, where an oxide film composed essentially of Al is formed. The amount of diffusion of Al is increased in the part requiring the utmost corrosion resistance by bringing the supporting body into contact, by which concentration and film thickness are increased. Because the corrosion resisting film composed essentially of Al is formed by using Al component in the jig as well as Al component in the materials to be treated, the decrease in Al component in the materials to be treated can be controlled and electromagnetic parts free from deterioration in magnetic properties can be mass-produced. |
