| 摘要 |
PROBLEM TO BE SOLVED: To easily and inexpensively obtain rare earth alloy powder having a high aspect ratio by subjecting acicular powder contg. Fe as essential components to surface treatment with a rare earth elemental complex, a transition metal complex and a B complex with acetylacetonate as ligands and executing heat treatment in a reducing atmosphere. SOLUTION: Acicular powder contg. Fe of goethite, hematite, magnetite or the like as eccential components and having about 12 to 22 aspect ratio is stirred in isopropyl alcohol together with an R (rare earth elements including Y) complex, a T (transition metal) complex and a B (boron) complex, and surface treatment is executed. The powder is, if required, added with a reducing assistant such as metal Ca powder or the like, and heat treatment of about 700 deg.C×4 hr is executed in a reducing atmosphere of Ar or the like. In this way, the magnetic powder of acicular R.T.B series rare earth alloy powder having about >=10 aspect ratio is obtd. By making the magnetic powder into a powder magnetic core or the like, its magnetic properties such as magnetic permeability can be improved. |
