Ion-induced amorphization in ceramic materials

Amorphization induced by swift heavy ions is discussed, the main features are reviewed and explained by the author's model. In Al2O3 and MgAl2O4 the recrystallization reduces considerably the track diameters. The threshold electronic stopping power for amorphization Set can be estimated reliably for these solids from the position of the amorphous-crystalline boundary formed at high ion fluences. The results are in good agreement with the predictions of the model. Experiments on CeO2 and UO2 are discussed. Estimates of Set are made for β-Si3N4, CeO2, pure ZrO2, ZrSiO4, and UO2, and 10.1 > Set > 6.2 keV/nm is obtained at room temperature for fission fragment energies. At about 1000 °C operation temperature, Set is reduced by about 35-50%. No amorphization is expected by ion bombardment in AlN, SiC (semiconductors) and MgO (ionic crystal).