Effect of structural-phase composition on magnetic properties of iron powders ground in carbonaceous medium doped with surface-active substance

In the process of intense grinding of iron powders in heptane with addition of oleic acid, the particles' dimensions reduce, their shapes change, and the particles are saturated with carbon, oxy gen, and hydrogen atoms, which diffuse to the regions of mosaic block boundaries and form weakly ordered dusters and iron-based phases. The coercive force increases from 8.5 to 92 A/cm as a result of grinding. In the process of anneal, ordered phases Fe3C and Fe3O4 are produced from disordered clusters and phases, which leads to an increase in the coercive force to 220 A/cm.