MICROSTRUCTURE OF NANOCRYSTALLINE TIO2 AND NI AT DIFFERENT DEGREES OF COMPACTNESS

The change of the microstructure of nanocrystalline TiO2 and Ni as a function of the compaction procedure was measured by small-angle neutron scattering. The scattering cross section is attributed to contributions from crystallites separated by interfacial regions and to voids as well as to correlations in the spatial arrangement of the different structural components. For Ni there is no drastic change in the scattering cross section for the compacted nanocrystalline solid compared with the as-prepared disperse material. For TiO2 the scattering cross section changes substantially during compaction, caused by changes in volume fractions and size distributions of the different components.