Microstructure and texture evolution of TRC A8006 alloy by homogenization

Abstract

The microstructure and texture evolution of twin-roll cast A8006 alloy by homogenization were characterized using scanning and transmission electron microscopy, and the microhardness was tested as well. According to the relationship between dendritic arm spacing and cooling rate the cooling rate of the as-cast twin-roll cast A8006 sheet of 6 mm in thickness was estimated as 1.48×10³ K·s⁻¹. It is found that the grains and the nanostructural precipitates of the twin-roll cast sheet become coarser after homogenization at 580°C for 4 h in comparison with those after homogenization at 500°C for 8 h. The textures formed after cold rolling and became weaker during homogenization. The increase in hardness of the as-cast twin-roll cast sheets is related to the supersaturated α-Al solid solution and fine microstructure, but the decrease in hardness after homogenization can be attributed to the coarsening of grains and Al₆Fe(Mn) precipitates.

Keywords

aluminum alloys / homogenization / microstructure / textures / hardness

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