Publication at Faculty of Mathematics and Physics |
2014
Abstract
A variable-energy slow-positron beam was applied to the investigations of the tetragonal yttria-stabilised zirconia (YSZ), the YSZ co-doped with small amount of Cr2O3. The initial nanopowders exhibiting the mean particle size of approximate to 20 nm were prepared by co-precipitation technique.
Prior the sintering, the nanopowders were calcined and compacted using a pressure of 500 MPa. The ordinary shape parameters of the Doppler-broadened annihilation peak and the relative positronium 3 gamma-fractions were determined as functions of positron energy.
The results are consistent with a remarkable sintering-induced grain growth and disappearance of porosity which is driven out from the sample interior toward a thin subsurface layer.