Delay in homogenization of Al-4.5%Cu alloy having feather crystals

Abstract

Some factors which may cause delaying homogenization time in feather crystals than that in columnar crystals of Al-4.5%Cu alloys were discussed. The diffusion rate of Cu atoms in aluminum is independent of diflusion direction, grain boundary area, twin-plane and dislocation density in the diffusion experiment using aluminum/eutectic diffusion couples. The difference between homogenization rates in columnar and feather crystals is attributed to the difference in distribution of the second phase in the feather and columnar crystals.