| 摘要 |
PURPOSE: To obtain an R-Fe-B-C based permanent magnet material excellent in corrosion resistance by filling a mold with fine powder of an R-Fe-B-C based alloy having a specified mean particle size at a specified filling density, inverting a specified pulse field repeatedly, subjecting the fine powder to hydrostatic press, sintering and aging thereby enhancing the orientation. CONSTITUTION: The magnet material principally comprises 10-30at% of R (at least one kind of rare earth element including Y), 4-15at% of B + C (B is 2 at% or less), and the remainder of Fe (one or two kind of Co and Ni substitutes for Fe). A mold is filled with fine powder of magnet material having mean particle size of 1.0-10μm at a filling density of 1.4-3.5g/cm<3> and a pulse field of 10kOe or above is applied instantaneously while being inverted for the purpose of orientation. It is then subjected to cold hydrostatic press, sintering and aging thus producing an R-Fe-B-C based permanent magnet material excellent in corrosion resistance. |
