Effect of iron on the microstructure and mechanical properties of the spray-formed and rotary-swaged 319 aluminum alloy

摘要

The influence of iron additions (0.8, 1.2, and 1.5wt.%) on the microstructure and tensile properties of the 319 aluminum alloy processed by spray forming and rotary swaging was investigated. The spray-formed deposits were rotary-swaged at 573K with an area reduction ratio of 5:1. Room temperature tensile tests showed a substantial increase of elongation at fracture (5.5 to 8%) when compared to the values observed for the iron-containing conventionally cast counterpart (0.6%). The high values of elongation at fracture were obtained due to the significant microstructural refinement and decrease of volumetric phase fraction, especially the iron-rich intermetallics, promoted by the combination of spray forming and rotary swaging. Therefore, this processing route significantly reduces the deleterious effect on the ductility caused by the iron content and the presence of -AlFeSi intermetallic phase in hypoeutectic Al-Si alloy.