Journal Article

Effect of Alloy Composition on the Dendrite Arm Spacing of Multicomponent Aluminum Alloys

Easton, Mark, St John, David, Davidson, Cameron

2010

Overview

Predictions of secondary dendrite arm spacing (SDAS) for multicomponent aluminum alloys using a dendrite ripening model are compared with experimental observations. For six of the seven alloys studied, the predicted SDAS was within 20 pct of the measured SDAS. It was found that the final SDAS was dependent upon both the solidification time and the solute profile of the solidifying alloys. It is interesting that while the solidification times and the solute segregation during solidification varied significantly over the range of alloys, these two factors largely canceled each other out so that the predicted SDAS did not vary much between the alloys. The experimental and modeling results show that elements causing high constitutional undercooling near the beginning of solidification, e.g. , Ti, which reduces the grain size substantially, have little effect on the SDAS. Instead, it was found that elements that strongly partitioned toward the end of solidification were more effective at restricting SDAS coarsening.

• Publisher: Springer US,Springer,Springer Nature B.V
• Subject: Alloys / Applied sciences / Characterization and Evaluation of Materials / Chemistry and Materials Science / Exact sciences and technology / Materials Science / Mechanical properties / Metallic Materials / Metallurgy / Metals. Metallurgy / Nanotechnology / Structural Materials / Studies / Surfaces and Interfaces / Thin Films