Abstract
A recent investigation has confirmed that solute atoms segregated to the interfaces between aluminum and θ′-Al2Cu can extend the stability of metastable θ′ to higher temperatures. Herein, we present an extensive first-principles database of the segregation energies of 34 elements to the Al/θ′ interface and identify key descriptors that can guide the design of higher temperature Al-Cu alloys. We find that the segregation energies are strongly correlated with the size and volume of solute atoms and their solubilities within θ′. We provide a physical/chemical basis to the experimentally observed elemental hierarchy in terms of the ability of individual elements to stabilize the Al/θ′ interface. Finally, we suggest a new microalloying strategy that offers opportunities to further increase the critical temperature limit of Al-Cu alloys.
| Original language | English |
|---|---|
| Pages (from-to) | 327-340 |
| Number of pages | 14 |
| Journal | Acta Materialia |
| Volume | 141 |
| DOIs | |
| State | Published - Dec 2017 |
Funding
This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). Research was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory , managed by UT-Battelle, LLC, for the U. S. Department of Energy. Early calculations were supported by the U. S. Department of Energy , Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office, Propulsion Materials Program. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725 .
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | DE-AC05-00OR22725 |
| Office of Science | |
| Office of Energy Efficiency and Renewable Energy | |
| Oak Ridge National Laboratory |
Keywords
- Al-Cu alloys
- Correlation analysis
- Density functional theory
- First-principles calculations
- Interface
- Solute segregation
- θ′-AlCu