Structure and magnetic properties of chemically prepared mixtures of crystalline and amorphous Fe(B) nanoparticles

A fine dispersion of crystalline and amorphous Fe(B) nanoparticles has been chemically prepared and its structural and magnetic properties compared to those of the corresponding single phase nanoparticles. The coercivity of the as-prepared dispersion was intermediate between that of the single phase crystalline and amorphous nanoparticles but less than expected from a simple rule of mixtures. Moreover, after annealing at temperatures below the crystallization temperature of the amorphous phase, the coercivity of the dispersion was reduced significantly below that of the single phase amorphous nanoparticles suggesting a modified interparticle interaction arising from the characteristic nanostructure of the dispersion. (c) 2005 American Institute of Physics.