Melt-spun NdFeB powders can be formed into a number of different types of permanent magnet for a variety of applications in the electronics and automotive industries. The melt-spinning process produces powder with a fine, uniform array of nano-scale Nd2Fe14B grains. These powders can be net-shape formed into isotropic polymer-bonded magnets or hot formed into fully dense magnets. This paper discusses the influence of heavy rare-earth elements and microstructure on the magnetic performance, thermal stability and material cost of NdFeB magnets. It is demonstrated that melt-spun nanocrystalline NdFeB magnets are less dependent on heavy-rare-earth elements for high-temperature performance than the traditional 5-10 μm grainsized sintered NdFeB magnets. In particular, hot-pressed melt-spun magnets are an attractive, low cost solution for applications that require thermal stability up to 175-200°C.
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