Permanent magnet alloy with good magnetic stability

摘要

The composition is based on iron and/or cobalt with the addition of boron and one or more rare-earth metals. To improve the coercive force, 0.1-0.3 wt.% of gallium and/or terbium (Tb) is added. The proportion of rare-earth metals is chosen such that a binder phase rich in neodymium amounts to less than 2.5% of the alloy. The magnetic stability is enhanced so that with an opposing field of the order of 5 kA/cm a reduction in remanence below 8% is achievable. The addition of Tb is undertaken by powder-metallurgical admixture of a Tb compound.