R-T-B BASED RARE EARTH PERMANENT MAGNET

文件类型：PDF文档
文件大小：284K
PROBLEM TO BE SOLVED : To provide an R-T-B based rare earth permanent magnet which achieves high magnetization rate in a low magnetizing field with its magnetization characteristics curve found, in a lower side of the magnetizing field/higher magnetization rate range. SOLUTION : The R-T-B based rare earth permanent magnet is a sintered body, comprising a main phase comprising an R2T14B phase (wherein R denotes one or two or more rare-earth elements containing Y and T denotes one or two or more kinds of transition metal elements essentially comprising Fe, or Fe and Co) and a grain boundary phase containing more R than the main phase. With Pc (permeance coefficient) being 2, provided that f1 is the total flux generated upon the application of an effective magnetic field of 240 kA/m (where the effective magnetic field = applied field - demagnetizing field), that f2 is the total flux generated upon the application of an effective magnetic field of 800 kA/m, and that f3 is the total flux generated upon the application of an effective magnetic field of 2, 000 kA/m, the magnetization rate (a) (=f1/f3×100) is 40% or higher and the magnetization rate b (=f2/f3×100) is 90% or higher. COPYRIGHT : (C)2006, JPO&NCIPI