STRUCTURAL AND MORPHOLOGICAL-CHANGES DURING THE MECHANICAL ACTIVATIONOF NANO-SIZE PARTICLES

Studies on changes in the morphology and structure of nanocrystalline ZnFe2O4, alpha-Fe2O3 and gamma-Al2O3 have shown that at first stages o f mechanical activation the activated crystals increase in size. The g rowth of crystals may be accompanied by change in physical properties of the activated substance. In the case of mechanical activation of al uminium oxide, this is a phase transition. The formation of structural defects during mechanical activation of the substances under study pr oceeds only after the crystals reach a definite size (of the order of 20 Mm).