Abstract:In order to obtain high-performance bonded NdFeB magnets, NdFeB powders containing coupling agent and binder were warm compacted. The influences of pressure, temperature, the kind and the content of binder on the density and performance of bonded NdFeB magnets were explored in the temperature range of 70-110 ℃. The results show that the relations between compaction pressure and green density of the NdFeB powder with 0.5% coupling agent blending 0.6% binder (mass percent) is in accordance with HUANG Pei-yun’s equation with the compaction module of 3.57 MPa and the nonlinear exponent of 0.21. With the increase of temperature and pressure, the density and the maximum magnetic energy product of the bonded NdFeB magnets increase first and then decrease. The density of magnets decreases rapidly when the mass percent of the binder exceeds 1.0%. Using the identical temperature, pressure and the content of binders, the magnets with the addition of semisolid E44 binder has higher density than those with E51 and CYD. The bonded NdFeB permanent magnet material with the density of 6.7 g/cm3 and the maximum magnetic energy products of 104 kJ/m3 is obtained at 80 ℃.
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