On the generation and motion of grain boundary dislocations in steel

Abstract

Electron microscopy of a 0.2% C Nb-steel slightly deformed at various temperatures has given additional evidence for generation and conservative movement of dislocations in grain boundaries. These phenomena, which seem to occur preferentially in the range 250°C-300°C, strongly suggest that grain boundary sliding in metals may receive an important contribution from the conservative movement of grain boundary dislocations, as has been put forward by Gleiter, Hornbogen and Bäro (1968) and Gleiter (1970), even though these processes are probably confined to limited grain boundary areas.