| About this Abstract |
| Meeting |
MS&T23: Materials Science & Technology
|
| Symposium
|
Light Metal Technology
|
| Presentation Title |
Role of Alloying Elements and Solidification Conditions on the Evolution of Fe-rich Intermetallic Phases in Recycled Al-Si Alloys with Higher Fe |
| Author(s) |
Nagasivamuni Balasubramani, Michael Moodispaw, Gabriel Garcia, Chuan Zhang, Alan Luo |
| On-Site Speaker (Planned) |
Nagasivamuni Balasubramani |
| Abstract Scope |
In secondary Al-Si alloys, Fe content (0.9-1.0wt.%) degrades the mechanical properties by the formation of brittle, acicular-shaped Fe-intermetallic phases. Micro-additions of manganese promote script type, less-harmful Fe-intermetallic phases, improving the tensile elongations of secondary aluminum alloy castings. However, achieving higher elongation is more challenging with the overall high fraction of intermetallics in the microstructure. This study investigates the application of CALPHAD (CALculation of PHAse diagrams) approach to design micro-alloying additions such as Mn, Sr and Cr. An improved thermodynamic model has been used to predict the formation of primary Fe-intermetallic phases, overall phase fractions, phase stability regions and sludge formation temperatures for Cr addition. The effect of cooling rate Fe-intermetallics was studied using wedge-type mold (1.5-60°C/s) and Cu-chill block representing the in-cavity and shot sleeve solidification conditions respectively. The role of microalloying, solidification conditions on the morphologies of Fe-intermetallic phases and mechanical properties are discussed. |