Grain-boundary plane orientation dependence of faceting–roughening transition in Au grain boundaries under electron-beam irradiation

Abstract

Grain boundaries act to absorb and annihilate point defects generated by high-energy particles for polycrystalline nuclear materials. Thus, understanding the effect of irradiation of high-energy particles on the grain-boundary structural change is prerequisite to develop nuclear materials with desirable properties. It is expected that such an effect would be different for different GB characters. To explore the probability, we examine grain boundaries with twist and tilt components with the same misorientation relationship of [1 0 0]/45o in Au as a model system at a high-voltage transmission electron microscope with an acceleration voltage of 1250 keV. It is observed that, under the same irradiation condition, the tilt GB undergoes roughening while the twist one became faceted.