MAGNETIC AFTEREFFECT AND MAGNETIZATION PROCESSES OF NANOCRYSTALLINE ALPHA-FE/ND2FE14B 2-PHASE MAGNET ALLOYS

Magnetic aftereffect and magnetization process of melt-spun nanostructured alpha-Fe/Nd2Fe14B two-phase alloys have been investigated, The heat-treated flakes composed of nanoscaled grain size show enhanced magnetic properties due to the intergranular exchange interaction similar to the exchange-spring behavior, The magnetization shows a logarithmic decay with the elapsed time in a steady field, being consistent with the Barbier plot and analytical results. The activation volume increases with increasing content of soft iron. The dc-demagnetization remanence data elucidate the irreversible demagnetization process. The soft iron phase, being responsible for reversible magnetization (M(rev)), exchange-couples with the hard phase and lessens the M(rev).