The invention relates to the technical field of
neodymium-iron-
boron magnets, in particular to a
neodymium-iron-
boron rare earth magnet and a preparation method thereof.The
neodymium-iron-
boron rare earth magnet is a sintered neodymium-iron-boron permanent
magnet and comprises a main phase, a two-particle
grain boundary phase and a triangular area
grain boundary phase; the main phase comprises an R2T14B phase, R refers to at least one of Nd and Pr, T refers to Fe, and Co at least contains Fe; the two-particle
grain boundary phase comprises a grain boundary
copper-rich phase, and / or a needle-shaped ZrBx phase with the width of 10-50 nm, and / or a needle-shaped TiBx phase with the width of 10-50 nm; the triangular region grain boundary phase comprises an FCC type NdOx phase, an RCu phase, an RGa phase, an R-rich phase, a 6: 14 phase and / or a needle-shaped ZrBx phase with the width of 10-50 nm and / or a needle-shaped TiBx phase with the width of 10-50 nm, the neodymium-iron-boron
rare earth magnet does not contain heavy rare earth and is good in uniformity, and the coercive force and residual
magnetism can be regulated and controlled through the design of the grain boundary phase.