Publication at Faculty of Mathematics and Physics |
2007
Abstract
High-resolution positron lifetime and coincidence Doppler-broadening measurements on the yttria-stabilised zirconia compacted nanopowders, differing in phase, stabiliser content and preparation conditions, are reported. The nature of defects observed in these materials is discussed on the basis of available experimental data and their comparison with theoretical calculations.
It is concluded that positrons annihilate mainly in vacancy-like defects at grain boundaries and in larger open-volume defects associated with triple points. A fraction of positrons annihilating in mesopores of approximate to 2.5 nm diameter was also detected.