High-resolution and conventional electron microscopy study of a Sigma=3, [101]{121} twin grain boundary in molybdenum

Complete structural analysis of a Mo bicrystal containing a Sigma =3, [101](1 (2) over bar1)(A) grain boundary (GB) was achieved by means of transmission electron microscopy from the microscopic to the nanoscopic level. Secondary GB dislocations compensating a small deviation from the exact Sigma =3 concidence were observed and their character was determined. Rigid-body displacements (RBDs) were determined directly from high-resolution electron microscopy images using samples with surface normal parallel and perpendicular to the tilt axis. Measured values of RBDs are compared with recent theoretical calculations.