Remanence enhancement in composite magnets of micrometre Sm-Fe-N grains and nanometre Fe particles

We report the hard magnetic behaviour of composite magnets prepared by directly mixing micrometer Sm-Fe-N grains with micrometer iron particles and nanometer iron particles, respectively. Remanence enhancement has been found in composite magnets prepared by directly mixing the micrometer Sm-Fe-N grains with nanometer iron particles. Our experimental results indicate that for remanence enhancement to occur in composite materials the size of the soft magnetic phase involved must be nanometer, while the particle size of the hard magnetic phase involved need not be limited to nanometer scales. (authors)