Grain boundary film thicknesses in superplastically deformed silicon nitride

摘要

The thickness of intergranular films in polycrystalline β-Si_2N_4 ceramics, both before and after superplastic deformation, has been systematically investigated using high-resolution transmission electron microscopy. In char- acterizing the film thickness, care was taken to correlate the grain boundary orientation with the direction of the compressive stress applied during the hot-pressing and the superplastic deformation.