| 摘要 |
PURPOSE:To obtain an anisotropic permanent magnet assuring good machinability, high coercive force, thermal stability and magnetizability by executing the processing by the hot press or hot processing machine of HIP to a particular alloy for which the average crystal grain size of molded item after the end of the final processing is specified. CONSTITUTION:An anisotropic permanent magnet consisting of the R-Fe-B-(M) system alloy (wherein R is a kind or two or more kinds of rare earth elements including Y and moreover combination of a kind or two or more kinds of Si, Nb, Al, Dy, Zn as the additive element (M)) with the average crystal grain size of the final molded item of 0.01-0.5 mum. In these alloys, R is 11-18 atom%, B is 4-11 atom%, M is 0.25-3 atom% and remainder is Fe and inevitable impurity. This alloy is also obtained by molding frakes or powder obtained by the melt quick cooling method into a highly densed material with a hot press and then by the warm upsetting. A magnet having improved magnetic characteristic without any internal distortion can be obtained in this way. |
