About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
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Heterostructured and Gradient Materials (HGM VI): Principle, Processing and Properties
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Presentation Title |
Plastic Deformation Mechanisms of Rapidly Solidified Al-Si Eutectic |
Author(s) |
Jian Wang, Wenqian Wu, Arkajit Ghosh, Amit Misra |
On-Site Speaker (Planned) |
Jian Wang |
Abstract Scope |
Al-Si cast alloys have been studied as structural materials due to their excellent castability, low thermal expansion, good wear and corrosion resistance. Al-Si cast alloys are usually composed of α-Al and Al-Si eutectic. Extensive experimental studies demonstrated that Si flakes cannot significantly improve mechanical properties of Al-Si cast alloys. We demonstrated that the weak strengthening effect associated with Si flakes is attributed to thermomechanical properties of Al-Si interfaces besides their morphologies. To conquer the weakening interface effect, nanoscale Si fibers formed in rapidly solidified Al-Si eutectic, forming two typical of dual-phase microstructures, heterogeneous structure and fully eutectic structure. Both structures exhibit high strength and good plasticity. By characterizing microstructures before and after deformation and conducing atomistic simulations of deformation events, we revealed unusual plastic deformation mechanisms in nanoscale Si fibers, which was promoted by pre-existing twin boundaries and enabled by local stress concentration due to dislocation loops around fibers. |
Proceedings Inclusion? |
Planned: |