Annealing effect on relaxor behaviours of spark plasma sintered Pb(Sc1/2Nb1/2)O3 superfine ceramics

Relaxor ferroelectric Pb(Sc1/2Nb1/2)O-3 (PSN) superfine ceramics were fabricated by spark plasma sintering process and subjected to an annealing in oxygen ambience at a low temperature of 500 degrees C. The microstructure of the PSN ceramics was examined by X-ray diffraction and scanning and transmission electron microscopy, while the dielectric properties were measured in the range of 25-200 degrees C. The dielectric measurements revealed a reverse change in the frequency dispersion Delta T and diffusive factor lambda as annealing extended. Transmission electron microscopy observation and conductivity measurement revealed that the uncommon performance in relaxor properties could be attributed to the complex effects of oxygen vacancies and domain structures induced by the annealing.