About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
|
Heterostructured and Gradient Materials (HGM IV): Tailoring Heterogeneity for Superior Properties
|
Presentation Title |
Origin of Enhanced Ductility in Laser Rapid Solidified Heterogeneous Hypereutectic Al-20Si Alloy: Slip Interactions between Soft Al Matrix and Hard Si Fibers? |
Author(s) |
Huai-Hsun Lien |
On-Site Speaker (Planned) |
Huai-Hsun Lien |
Abstract Scope |
Micropillar compression revealed enhanced flow strength for laser rapid solidified (LSR) heterogeneous Al-20Si as compared to as-cast Al-12Si. This strength increase can be attributed to the refined Si fiber with diameter averaging 50 nm and reduced interfiber spacing with similar length scale. In addition, much higher degree of uniform deformation was observed for LSR alloy. Postmortem SEM and TEM suggested co-deformability between Al matrix and Si fibers, which dislocations was observed in both phases. Several length scales exist within the LRS Al-Si alloy: the μ m-size primary Al dendrites, which is embedded in nm-size Al-Si ultrafine eutectic, and nanotwins within the Si fibers. in-situ SEM and in-situ TEM further reveal the deformation behavior and slip mechanisms for LRS microstructures. These findings are crucial to understanding the interactions between nanoscale hard soft phases and to constructing the microstructure to mechanical property map for tailoring the mechanical properties. |
Proceedings Inclusion? |
Planned: |
Keywords |
Aluminum, Mechanical Properties, Characterization |