Abstract
The grain boundary relaxation of Al–Fe alloys was studied by internal friction measurement. The relaxation strength of the grain boundary peak increased significantly as grains grow from equiaxial to bamboo-type grains by annealing at high tempetatures. The peak of the bamboo structure (BP) resembles in some respects with the HTP observed in the previous work, though its peak temperature and activation energy are much lower than those of the HTP reported on pure aluminium. This peak is suppressed significantly when a small amount of iron precipitates in the grain boundaries. All of the features of the BP may be accounted for on the basis of the mechanism of grain boundary sliding.
