| 摘要 |
PURPOSE:To contrive improvement in magnetic characteristics of the titled magnet material, especially in coersive force and squareness, by a method wherein FeBR is used as the base, a part of Fe is replaced by Co, Fe-Co-B-R-M alloy powder of fixed composition range containing additive element M (V, Nb, Ta, Mo, W, Cr and Al) is formed, sintered and then a heat treatment is performed. CONSTITUTION:The alloy powder has the composition (FeBRM composition) consisting of 8-30 atomic percentage of R (provided that R consists of at least one kind of rare- earth element containing Y), 2-28% of B, 50% or less of Co (provided that 0% is excluded), one kind or two or more kinds of additive element M of less than the prescribed percentage (provided that M:0% is excluded, M is V:9.5% or less, Nb:12.5% or less, Ta:10.5% or less, Mo:9.5% or less, W: 9.5% or less, Cr:8.5% or less and Al:9.5% or less, and the total quantity of M when two kinds or more of M are contained is less than the prescribed percentage of that having the maximum value among each element contained in M and the remainder substantially consisting of Fe. The alloy powder of 0.3-80mum in average particle size in above-mentioned constitution is formed, sintered at 900-1,200 deg.C in a non-oxidizing or reducing atmosphere, and a heat treatment is performed at the temperature between 350 deg.C and the sintering temperature or below, thereby enabling to obtain the FeCoBRM permanent magnet material having excellent magnetic characteristics. |
