Abstract：The relationship between the NdFeB powder size and the sintering temperature, the magnetic properties was researched. The results showed that the sintered NdFeB’s intrinsic coercivity increases with the decreased powder size. However, when the powder size decreases further to lower than 2. 4 μm, the coercivity cannot be improved any further but starts to decrease. In addition, the sintered NdFeB with different Co content through the grain refinement treatment was investigated. The weight loss of the magnets decreases with the increasing of the Co content.
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2015, Vol. 22 
