| 摘要 |
PURPOSE:To develope a rare earth permanent magnet alloy having superior magnetic properties by controlling the composition of a cellular structure in an R2Co17 type rare earth magnetic alloy with specific composition. CONSTITUTION:An ingot of an alloy having a composition consisting of, by weight, 24-28% R (one or more kinds among rare earth elements), 10-20% Fe, 3-6% Cu, 2-4% Zr, and the balance Co is crushed, pulverized, and compacted into desired shape in a magnetic field. The resulting green compact is heated, e.g. to 1100-1250 deg.C to be sintered, and subjected to solution heat treatment at a temp. lower by 0-50 deg.C than the above temp. Subsequently, ageing treatment is applied at 700-950 deg.C to form a fine cellular structure, and the content of Cu contained in the R2Co17 phases constituting the cells is controlled to 1-3 atomic %. By this method, the R2Co17 type rare earth permanent magnet improved in magnetic properties as to have >=20KOe coercive force can be produced. |
