About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Aluminum Alloys, Characterization and Processing
|
Presentation Title |
Microstructure and Mechanical Properties of an Al-Mn-Si Alloy Microalloyed with Post Transition Metals |
Author(s) |
Amir R. Farkoosh, David C. Dunand, David N. Seidman |
On-Site Speaker (Planned) |
Amir R. Farkoosh |
Abstract Scope |
We demonstrate that a small addition of a low-melting point element such as Sn (0.02 at.%), within the impurity tolerances of commercial aluminum alloys, to an Al-0.5Mn-0.3Si (at.%) model alloy, turns this non-heat-treatable (i.e., with negligible precipitation strengthening) alloy into a heat treatable (i.e., precipitation strengthened) alloy with high strength, creep, and coarsening resistance. The small Sn additions refine the α-Al(Mn,Fe)Si-precipitate distribution significantly, which is related primarily to the formation of Sn-rich nanoprecipitates at intermediate temperatures (~200 oC). These nanoprecipitates, which exhibit an unanticipated superheating phenomenon at temperatures above their melting point, act as heterogeneous nucleation sites for Mn-Si-rich nanoprecipitates – the quasi-crystalline precursors of the α-precipitate. We demonstrate that dispersion hardening by these Sn-modified α-precipitates is a highly efficient approach to designing creep-resistant aluminum alloys |
Proceedings Inclusion? |
Planned: Light Metals |
Keywords |
Aluminum, High-Temperature Materials, Mechanical Properties |