Ultra-Fast Current Aided Sintering of High Coercive Magnetic Powders and Composites

The paper refers to pulverization and sintering of the (Fe₈₀ Nb₆ B₁₄ )_0.88 Tb_0.12 high coercive alloy. The powder was sintered using the ultra-fast current aided method. It turned out that too long discharge time leads to appearing of a soft magnetic phase and simultaneously, decrease in coercivity of the compacted powder. Nevertheless, it was possible to establish preference technology parameters, preserving magnetic hardness of the alloy. As a final test, an impact of Co-powder addition on magnetic properties was studied. The introduced soft magnetic phase (about 20 wt. %) caused about 30% increase of magnetic remanence, which is a resultof direct exchange interactions between the two phases.