Synthesis of nanostructured iron oxides and new magnetic ceramics using sol-gel and SPS techniques

The original way of synthesis of nanostructured iron oxides and based on them magnetic ceramics via sequential combination of sol-gel and SPS technologies has been suggested. High quality of nanostructured iron oxides is defined by porous structure (Sspec up to 47,3 м2/г) and by phase composition of mixed and individual crystal phases (γ-Fe2O3/Fe3O4 и α-Fe2O3), depending on synthesis conditions. High-temperature SPS consolidation of nanostructured hematite powder, resulting in magnetic ceramics of high mechanical strength (fracture strength 249 MPa) has been investigated. Peculiarities of change of phase composition and composite’s microstructure in the range of SPS temperatures from 700 to 900 °С have been revealed. Magnetic properties have been studied and regularities of change of magnetization (Ms) and coercive force (Hc) values of the ceramics with respect to SPS sintering temperature have been described.