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Mixed powders of Bi2O3 and Fe2O3 are shown to yield single-phase, dense nanostructured polycrystals of BiFeO3 in reaction flash sintering experiments, carried out by applying a field of 50 V cm -1 and with the current limit set to 35 mA mm -2 . The furnace was heated at a constant rate with the reaction sintering taking place abruptly upon reaching 625 o C.Remarkably, an intermediate bismuth-rich phase of the oxide that forms just before reaching the flash temperature, transforms, and at the same time sinters, into single-phase BiFeO3 within a few seconds after the onset of the flash. The BiFeO3 so produced is electrically insulating, a property that is critical to its applications. This one-step synthesis of single-phase polycrystals of complex oxides from their basic constituents, by reaction flash sintering, is a significant development in the processing of complex oxides, which are normally difficult to sinter by conventional methods.

Titanium carbonitride (TiC x N 1Àx ) powders were obtained by high-energy ball milling of elemental titanium and carbon (activated carbon or graphite) in a nitrogen atmosphere. The formation of the carbonitride phase was controlled by adequately choosing the experimental conditions of the milling process. The stoichiometry of TiC x N 1Àx powders was modified by adjusting the titanium-to-carbon molar ratio. The composition and cell parameters of the carbonitride phases were determined. Microstructural characterization of these phases showed a nanocrystalline nature.