The effect of orientation on grain boundary migration and radiation-induced segregation under irradiation

To study the effect of orientation on grain boundary migration, a Fe-Cr-Ni alloy was electron irradiated using a high voltage electron microscopy (1000 kV), and in-situ observations on structural evolution and microchemical analyses were carried out. When the Fe-Cr-Ni alloy was irradiated, the nucleations of dislocation loops followed by voids were observed and at the same time when a grain boundary migration occurred. The compositional analyses after irradiation of an area including a grain boundary indicated nickel enrichment and chromium depletion near the grain boundary. It is suggested that when the radiation-induced point defects flow into the grain boundary, boundary migration and solutes redistribution are induced and the magnitudes depend on net point defects flow. (author)