Effect of Equal Channel Angular Pressing on Microstructure and Dislocation Strengthening of 3003Al Ingot

Equal channel angular pressing (ECAP) of 3003Al ingot has been performed at room temperature, with an imposed equivalent strain of similar to 0.5 for single pass, and the refinement/distribution of inclusions and the hardness/dislocation of the alloy were examined. The results show that the first pass ECAP processing refined the inclusions (AlFe (Mn)Si) of the alloy considerably, with the size variation from 5-15 mu m length/1-2 mu m width to 1-3 mu m length/1-2 mu m width. In addition to the refinement, the first pass ECAP processing improved significantly the distribution of the AlFe(Mn)Si inclusions, and introduced high density of dislocations, leading to similar to 66.7 % increase of hardness. It was found that with the increase of number of ECAP processing passes, the distribution of AlFe(Mn)Si inclusions were increasingly more uniform, while the size of inclusions, the hardness and dislocation density (dislocation strengthening) of the alloy kept almost unchanged. The present results demonstrate the possibility of ECAP as an effective tool to refine AlFe(Mn)Si inclusions of aluminum alloys.