TABLE OF CONTENTS G. SZENES
Department of General Physics, E tv s University, 1518 Budapest, P.O.Box 32 Hungary
Amorphization induced by energetic ions in insulators is discussed. The main features are reviewed and explained by the author's model. When recrystallization is negligible, the predictions of the track diameters and the threshold electronic stopping power for track formation S et are in good agreement with experimental data. In Al 2O 3, MgAl 2O 4 and UO 2 track recrystallization is considerable. Reliable S et values can be obtained for these solids from the measurements at high ion fluences, which are also in good agreement with the predictions. Estimates are made for ?-Si 3N 4, CeO 2, ZrO 2 and ZrSiO 4, as well. All values are in the range 10.1>S et>8.7 keV/nm and they are low enough for fission fragment damage in the above insulators. At about 1000 C irradiation temperature S et is reduced by about 35 50%. In AIN, SiC (semiconductors) and MgO (ionic crystal) no amorphization is expected.
Recently, the study of ceramic materials for inert matrices has grown more active. An important requirement is the stability of the proposed ceramics against the impact of fission fragments (ff), which can induce tracks (amorphous, recrystallized) and swelling. Irradiation with high fluences may induce complete amorphization. In insulators the threshold electronic stopping power for track formation S et is the main parameter characterizing the amorphization. In the present paper...
