The physical mechanisms of the growth and stability of charged dislocation loops were investigated in ceramic materials having very different-mass atoms (stabilized cubic zirconia) under different energies and types of irradiation conditions: 100 to 1000keV electrons, 100keV He+ and 300keV O+ ions. The anomalous formation of extended defect clusters (charged dislocation loops) was observed by TEM under electron irradiation subsequent to ion irradiation. It was demonstrated that very strong strain field (contrast) was formed near to charged dislocation loops. The dislocation loops grow up to a critical size and after then become unstable. The instability of the charged dislocation loop led to the multiplication of dislocation loops and the formation of dislocation network near to the charged dislocation loops. A theoretical model was suggested for the explanation of the growth and stability of the charged dislocation loop, taking the charge state of point defects. The calculated distribution of the modified strain field by the electrical field around the charged dislocation loops was stronger than that of non-charged dislocation loops. The obtained theoretical results for the modified strain field contrast and the critical radius of unstable charged dislocation loops were compared with observed experimental data.

Growth and Instability of Charged Dislocation Loops under Irradiation in Ceramic Materials. A.I.Ryazanov, K.Yasuda, C.Kinoshita, A.V.Klaptsov: Journal of Nuclear Materials, 2002, 307-311[2], 918-23