R-Fe-B TYPE SINTERED MAGNET AND METHOD FOR MAKING THE SAME

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The present invention relates to an R-Fe-B type sintered magnet comprising : a main phase of an intermetallic compound of R_2(Fe, (Co))_14B with boride phase such as Ti at grain-boundary triple junctions without R_1.1Fe_4B_4 compound phase; having a core/shell structure of the main phase coated by a grain-boundary phase containing an amorphous and/or fine crystalline R (R is a rare earth element mandatorily including Nd and Pr)-Fe(Co)-M_1(Si, Al, etc.) phase or the above R-Fe(Co)-M_1 phase and a crystalline of R having 50 at% or more, or an amorphous and/or fine crystalline R-M_1 phase with a surface coating rate of 50% or more for the main phase of R-Fe(Co)-M_1 phase; a width of the grain-boundary phase in the main phase 2 particles is 10 nm or more and 50 nm or more in average, and having an average particle diameter of 6 m or less; and a crystal orientation degree of 98% or more, and a magnetization of 96% or more. The R-Fe-B sintered magnet of the present invention provides coercivity having at least 10 kOe or more and a magnetization of 96% or more, without including Dy, Tb, and Ho.