High energy NdFeB permanent magnet improvement by critical elements substitution

JORGE M. LEVINGSTON; LUIS M. FABIETTI

Rosario - Santa Fe

Encuentro; XV Encuentro: Superficies y Materiales Nanoestructurados NANO 2015; 2015

CNEA

Duringthe last years extensive work has been carried out to lower the amount of rareearth components in hard magnetic materials such as SmCo and NdFeB alloys. Onepossible route is to couple a soft magnetic phase to them through exchangeinteraction. This idea has been proved successfully in the magnetic compositesNd$_{2}$Fe$_{14}$B.  These alloys kept,under the right processing conditions most of the energy product, depending onthe amount of iron added.  Themicrostructure responsible for such a behavior depends strongly on theprocessing method because the coupling exchange interaction happens in a narrowwindow of the grain size and the phase distributions. Unfortunately supplyconstraints and high prices of rare earth elements (which they are their thekey constituents) imposed by the major producing country, China (since 2010),has promoted the search for several potential alloys that could replaceNd-based permanent magnets with more abundant and less strategically importantelements.