A kind of ultrahigh magnetic energy product neodymium iron boron permanent magnet material and preparation method thereof

Abstract

The invention relates to the technical field of rare earth permanent magnet materials, in particular to an ultra-high energy product NdFeB permanent magnet material and a preparation method thereof, the composition of which is RE1xRE2yRE3zFqBoMp; wherein, RE1 is selected from rare earth elements Pr / Nd / Ho / Gd / Ce At least one of, RE2 is selected from at least one of the heavy rare earth elements Dy / Tb, RE3 is an additional rare earth metal or / and rare earth alloy, calculated based on the total mass of RE1, RE2, F, B, M, and its content accounts for For: 29wt%≤x+y+z≤33.5wt%, 0wt%≤y≤3wt%, 0wt%≤z≤2wt%; B is selected from at least one of boron and carbon, and its content is 0.85wt%≤ o≤1.2wt%; M is selected from at least one of Al / Cu / Zr / Nb / Ga / Si / Mo / Ti, and its content is 0.01wt%≤p≤1.5wt%; the rest is F, F At least one selected from transition elements Fe / Co / Ni.

Description

technical field [0001] The invention relates to the field of permanent magnet materials, in particular to an NdFeB permanent magnet material. Background technique [0002] With the development and research of NdFeB materials, the brittleness of NdFeB materials has plagued NdFeB manufacturers and processors. Especially in the pursuit of low cost, the original fine powder is getting finer and finer, making the brittleness of permanent magnet materials more and more difficult. It is becoming more and more obvious that the processing yield is low, especially in the research and development and production of ultra-high energy product materials. [0003] In the existing research, there is very little improvement in material brittleness. The principle of brittleness is mainly that transgranular fracture and intergranular fracture are easy to form during the hydrogen breaking process of NdFeB flakes. At the same time, because the material is a porous material, it is easy to form por...

AI Technical Summary

Problems solved by technology

[0005] Chinese Patent Publication No. 103177867A provides a kind of rare earth metal dehydrogenation at 830 ℃ ~ 860 ℃ heat preservation to below 50ppm after hydrogen absorption, and dehydrogenation at 400 ℃ ~ 420 ℃ after hydrogen absorption and crushing of rare earth iron boron composition. This scheme is actually in the original Rare earth is added on the basis of NdFeB to fill the pores to solve the problem of increased brittleness of permanent magnets; this invention requires new equipment investment, and the hydrogen content is less than 50ppm. Compared with the existing level of 1000ppm, the waiting time for dehydrogenation is long , because the hydrogen content is greatly reduced, the oxygen in the subsequent production process is more likely to contact and react with the powder, which is very unfavorable to the production of high coercive force products

Similarly, when targeting products with a thickness of less than 1mm or special-shaped products, there is still the same situation as the Chinese Patent Publication No. CN107910154A, which cannot effectively solve the problem of low processing yield, and adding tin to improve the brittleness of NdFeB materials is very limited

[0008] Chinese Patent Publication No. 104607634A provides a method for processing ring magnets, which improves the brittleness of ring products to a certain extent, but does not improve the brittleness of magnets from the perspective of materials

If the brittleness of the matrix itself is reduced, the processing yield will be higher for the same processing method. At the same time, the processing of this method is cumbersome, and there are many supporting tooling fixtures. It is very difficult to directly press the deformation of the ring product and cause the matching problem.

[0009] To sum up, the current three types of methods all have problems such as cost or insufficient improvement for the existing improvement of brittleness.

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