Interrelation between the compaction pressure of lithium carbonate and iron oxide powder mixture and efficiency of solid-phase synthesis of lithium pentaferrite are investigated. It is demonstrated that the temperature dependence of the degree of transformation during isochronous annealing for 60 min obeys the Arrhenius law. The effective activation energy of the process decreases when the compaction pressure increases from 0.4 (Р = 0) to 0.2 eV (Р = 202 MPa). A linear dependence between the degree of transformation and the specific magnetization of the mixture is observed at synthesis temperatures of 870-1070 K. No influence of the compaction pressure on the magnetic anisotropy field of synthesized spinel is revealed.

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A comparative analysis for different methods of compacting corundum-zirconia powders of different fineness, and also the effect of a plastifier on compaction efficiency are presented. It is shown that the most dense compacts are prepared with two-directional magnetic-pulse pressing. In view of this it is proposed to use two-directional magnetic-pulse pressing of oxide powders as the main compaction method in the production of corundum-zirconia nanoceramics.

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