Effect of grain boundary structure on diffusion-induced grain boundary migration in BaTiO3

Abstract

The effect of grain boundary structure, either rough or faceted, on diffusion-induced grain boundary migration (DIGM) has been investigated in BaTiO3. SrTiO3 particles were scattered on the polished surfaces of two kinds of BaTiO3 samples with faceted and rough boundaries and annealed in air for the samples with faceted boundaries and in H-2 for those with rough boundaries. In the BaTiO3 samples with rough boundaries, an appreciable grain boundary migration occurred. In contrast, grain-boundary migration hardly occurred in the BaTiO3 samples with faceted boundaries. The migration suppression observed in the sample with faceted boundaries was attributed to a low boundary mobility. The present experimental results show that DIGM is strongly affected by the boundary structure and can be suppressed by structural transition of boundaries from rough to faceted.