Microstructure Investigation on the Triple Junction with an Adjoining Twin Boundary in Nanocrystalline Palladium

By using high-resolution transmission electron microscopy, a [(1) over bar 10] triple junction (TJ) containing a twin boundary (TB) in nanocrystalline palladium has been observed along the common axis direction. Molecular statics calculation and imaging simulation were performed to determine the atomic structure of the TJ. The modeling structure exhibits that the adjoining TB is a distorted one, whilst other two adjoining grain boundaries (GBs) exist in steady equilibrium states. The present observation gives a clear example demonstrating that the adjoining TB can release the larger stresses residing at the junction.