1. A sintered Nd-Fe-B magnet consisting essentially of: rare earth element R, additive element T, iron Fe, and boron B, wherein said magnet comprises a rare-earth rich phase and a main phase of Nd2Fe14B crystalline structure, and wherein the numeric sum of maximum energy product (BH)max in MGOe and intrinsic coercivity Hcj in kOe is no less than 76, i.e., (BH)max(MGOe)+Hcj(kOe)?76,wherein said magnet comprises 28 to 32 wt % rare earth element R, 0-4wt % additive element T, 0.93-1.0 wt % boron B, with the balance of iron Fe, and impurities, wherein R is one or more elements selected from Y, Sc, and fifteen elements of lanthanide series,
wherein T is one or more elements selected from Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, Al, Zr, Nb, Mo, and Sn,
wherein the average crystalline grain size of said main phase is in a range from 5.0 ?m to 9.1 ?m, and
wherein oxygen content of said magnet is in a range from 1000 to 1625 ppm.