High angle grain boundaries as sources or sinks for point defects

A secondary grain boundary dislocation climb model for high angle grain boundaries as sources/sinks for point defects is described in the light of recent advances in the knowledge of grain boundary structure. Experimental results are reviewed and are then compared with the expected behavior of the proposed model. Reasonably good consistency is found at the level of present understanding of the subject. However, several gaps in knowledge still exist, and these are identified and discussed briefly.