| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
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Phase Stability in Extreme Environments II
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| Presentation Title |
Metastability-driven design of AM Al-based Superalloys |
| Author(s) |
Ying Yang, A. Plowkowski, Ke An, Alice E. Perrin, W. Zhong, Q. Ren, Indranil Roy, Yury Osetskiy |
| On-Site Speaker (Planned) |
Ying Yang |
| Abstract Scope |
Lightweight but strong materials offer great potential for increasing vehicle fuel efficiency while maintaining safety and performance. Forming dispersive tri-aluminide nanoprecipitates in a ductile Al FCC matrix is desirable to achieve excellent mechanical properties in light-weight Al alloys. However, to form a high-volume fraction of such precipitates with the desirable size, number density and distribution remains a challenge. In this work, the relative stability of the different tri-aluminide (Al3M) structures (such as L12, DO22, DO23) in Al-Zr and Al-Nb systems was assessed for their potential to form nanoscale cubic L12 precipitates in additively manufactured (laser powder bed fusion) alloys. SEM, TEM and APT were used to characterize the microstructure and the results show that the metastable L12 structure is highly competitive with the stable DO23 structure in the Al-Zr system, but much less stable than the DO22 structure in the Al-Nb system. The experimental results are in good agreement with the DFT and kinetic calculations. In-situ tensile test under neutron diffraction was used to study the mechanical behaviors and deformation mechanisms. Both alloys demonstrated a good combination tensile strength and elongation. This work provided a promising strategy for developing high strength Al alloys strengthened by a high-volume fraction nanoscale trialumides via additive manufacturing. |
| Proceedings Inclusion? |
Planned: |