Structural Disordering in Magnesium Aluminate Spinel Compounds under Ion-Beam Irradiation

Abstract

ABSTRACTHigh Angular Resolution Electron Channeling X-ray Spectroscopy (HARECXS) of analytical electron microscopy was employed in quantitative analysis of irradiation-induced structural disordering in MgO·n Al2O3 spinel compounds irradiated with 1 MeV Ne+ ions and 200 MeV Xe14+ ions. The results successfully show the disordering behavior in MgO·n Al2O3 as a function of composition and irradiation condition. It has been revealed by HARECXS that 1 MeV Ne+ irradiation at 873 K causes significant cation-disordering in the pre-peak damaged area where no indication is recognized in conventional TEM observation. Displacement of O2- ions is also recognized in heavily damaged areas. Irradiation with 200 MeV Xe14+ swift ions, on the other hand, forms structurally-disordered cylinders of 4 nm in diameter along their tracks. HARECXS profiles indicate that the disordering takes place over extended areas of about 10 nm in radius centered on the ion tracks.