Abstract
Microstructure and grain growth characteristics of the pre-deformed Al–Bi alloys annealed at 773 K are investigated mainly by scanning electron microscopic (SEM) observation. It was shown that while there are a small amount of very fine liquid Bi particles in the grains, the Bi particles on the grain boundaries grow dragged by the moving grain boundaries. The grain growth is significantly restricted by the dragging effect. Origin of this dragging phenomenon can be explained with mixture effects of the grain boundary curvature and the surface energy of the intragranular Bi particles. By a quantitative analysis it was confirmed that the diffusion of Al atoms in the liquid Bi particles on the grain boundaries rate-controls this dragging effect.
