A heavy rare earth-free sintered NdFeB

Abstract

The invention relates to the field of permanent magnetic materials and discloses a heavy rare earth-free sintered NdFeB. The raw material comprisesa main phase alloy and an auxiliary phase alloy. Themass composition of the elements in that main phase alloy is PraNdbTMcFe100-a-b-c-dBd, wherein TM is one or more of Nb, Al, Cu, Co, Ni, Ga, Zr; 27 <= a, b <= 32, 0 <= c <= 10, 0.7 <= d <= 1. 1, the rest is Fe and inevitable impurities; The mass composition of the elements in the auxiliary phase alloy is NdmFen alloy, m+n=1; The mass of the auxiliary phase alloy is 0.5%-4wt% of that of the main phase alloy. The invention can make the performance of the Nd-Fe-B magnet reach the magnetic performance which can be achieved by adding 1-3wt% of dysprosium into the Nd-Fe-B magnet prepared by the traditional process without using the heavy rare earth.

Description

technical field [0001] The invention relates to the field of permanent magnet materials, in particular to a heavy rare earth sintered NdFeB. Background technique [0002] Compared with other permanent magnet materials, sintered NdFeB permanent magnet materials have relatively high intrinsic coercive force and magnetic energy product, so they are widely used in electronic circuits, metal instruments, aerospace, medical machinery and other fields. The common ones are permanent magnet motors, speakers, computer disk drives, magnetic resonance imaging equipment instruments, etc. At the same time, high-performance NdFeB permanent magnet materials are widely used in modern industry and electronic technology, so that instruments and equipment tend to be miniaturized, thinned and energy-saving. [0003] Rare earth permanent magnets have been developing in the direction of high performance with high remanence and high coercive force. In order to improve the overall performance of Nd...