KENBIKYO Vol.52▶No.1 2017
■Seto Award

Transmission Electron Microscopy Studies on Radiation-Induced Structural Changes

Manabu Ishimaru

Abstract: Irradiation techniques using ion-, electron-, and laser-beams can realize atomic configurations far from the equilibrium state, the so-called metastable phases, which are difficult to be obtained by conventional material synthesis techniques. The physical properties of materials strongly depend on atomic arrangements, and therefore knowledge of atomistic structures is required to synthesize new structural and functional materials. In addition, understanding structural changes of matter under radiation environments is of technological importance to predict performance and lifetimes of materials and to avoid serious accident. We have examined radiation-induced structural changes of various materials using transmission electron microscopy. In this article, we report our resent studies on (1) thermally-induced corundum-to-spinel phase transformation in Zr ion irradiated Al2O3 and (2) the enhancement of radiation tolerance in nanostructured SiC.

Key words: Radiation damage, phase transformation, metastable phase, amorphous