Dislocation structure and segregation behavior at a (110)/[001] low-angle tilt grain boundary in magnesium oxide

Abstract

A dislocation in a crystalline material has dangling bonds at its core and strong strain field in its vicinity. Therefore, it has a potential to exhibit peculiar physical properties and resolving atomic structure of boundary dislocations is considerable significance. In this study, we investigated atomic structure of boundary dislocations in magnesium oxide (MgO) by using scanning transmission electron microscopy (STEM). MgO is a typical ionic material that has sodium chloride type structure. In order to introduce dislocations in the crystal, we fabricated low-angle grain boundaries by a diffusion bonding technique. Owing to this method, we can arrange dislocations periodically in the crystal and observe dislocation structures easily. It was found that characteristic structures of dislocations.