GRAIN BOUNDARY DISTRIBUTION IN MATERIALS SUSCEPTIBLE TO ANNEALING TWINNING

Grain boundary distributions in various materials with low and medium stalking fault energy subjected to different recrystallization annealings were investigated. It was established that grain boundary spectra in all these materials are similar. The main feature of these spectra is that most of the boundaries are Σ3n boundaries. A model grain boundary spectrum was obtained by computer simulation based on the assumption that Σ3n boundaries formed as a result of multiple twinning played a dominant role in the grain boundary ensemble. The model boundary distribution agrees well with the experimental data. The conclusion is made that in materials susceptible to annealing twinning most (or almost all) of the grain boundaries are Σ3n boundaries and the distribution of these boundaries characterizes some stable state toward which the grain boundary ensemble tends during its evolution