Campus Units
Materials Science and Engineering, Ames Laboratory
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
12-2019
Journal or Book Title
Materials Today Communications
Volume
21
First Page
100673
DOI
10.1016/j.mtcomm.2019.100673
Abstract
The thermodynamic landscape involving several metastable phases in the glass-forming Al-Sm system is assessed, integrating experimental measurements and first principles calculations into a comprehensive CALPHAD description. The phases examined here include Al41Sm5-η, Al60Sm11-ε, Al5Sm-θ, Al5Sm-π and Al4Sm-γ, having basis stoichiometries from 9 to 20 at% Sm, a range over which the Al-fcc and Al3Sm phases are stable. Amongst the metastable phases examined, our findings indicate that the Al41Sm5-η and Al60Sm11-ε phases comprise the convex hull of minimum formation energies at absolute zero. Competitive crystallization processes were investigated through situ X-ray diffraction and differential scanning calorimetry and used to assess relative stability within the overall landscape. Asserting thermodynamic scenarios consistent with our measurements, temperature-dependent Gibbs free energies for the metastable phases are proposed along with the corresponding constrained phase diagrams, comprehensively showing metastable phases and associated invariant reactions. Assumptions and limitations of the proposed thermodynamic model are discussed with reference to available transport data.
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Copyright Owner
Elsevier Ltd.
Copyright Date
2019
Language
en
File Format
application/pdf
Recommended Citation
Zhou, S. H.; Meng, F. Q.; Kramer, Matthew J.; Ott, Ryan T.; Zhang, Feng; Ye, Zhuo; Jain, Shubhra; and Napolitano, Ralph E., "Metastable intermetallic phases in the Al-Sm system" (2019). Materials Science and Engineering Publications. 351.
https://lib.dr.iastate.edu/mse_pubs/351
Comments
This is a manuscript of an article published as Zhou, S. H., F. Q. Meng, M. J. Kramer, R. T. Ott, F. Zhang, Z. Ye, S. Jain, and R. E. Napolitano. "Metastable intermetallic phases in the Al-Sm system." Materials Today Communications 21 (2019): 100673. DOI: 10.1016/j.mtcomm.2019.100673. Posted with permission.