Abstract
Using synchrotron X-ray total scattering and empirical potential structure refinement modelling, we studied systematically in operando condition the disorder-to-order local atomic structure transition in a pure Al and a dilute Al-0.4Sc alloy melt in the temperature range from 690 °C to 657 °C. In the liquid state, icosahedral short-range ordered Sc-centred Al polyhedrons form and most of them with Al coordination number of 10–12. As the melt is cooled to the semisolid state, the most Sc-centred polyhedrons become more connected atom clusters via vertex, edge and face-sharing. These polyhedrons exhibit partially icosahedral and partially face-centred-cubic symmetry. The medium-range ordered Sc-centred clusters with face-sharing are proved to be the “precursors” of the L12 Al3Sc primary phases in the liquid-solid coexisting state.
Original language | English |
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Article number | 114484 |
Journal | Scripta Materialia |
Volume | 211 |
Early online date | 9 Jan 2022 |
DOIs | |
Publication status | Published - 1 Apr 2022 |
Bibliographical note
Funding Information:The authors would like to acknowledge the synchrotron X-ray beam time awarded by beamline I15 of Diamond Light Source (experimental No. EE20883-1); access to the University of Hull Supercomputer, Viper, and the technical support. Da Shu and Baode Sun also would like to acknowledge the financial support from the National Natural Science Foundation of China (Nos. U1832183 and 51821001). Shi Huang and Shifeng Luo also would like to acknowledge the financial support from the China Scholarship Council for their PhD study at University of Hull.
Funding
The authors would like to acknowledge the synchrotron X-ray beam time awarded by beamline I15 of Diamond Light Source (experimental No. EE20883-1); access to the University of Hull Supercomputer, Viper, and the technical support. Da Shu and Baode Sun also would like to acknowledge the financial support from the National Natural Science Foundation of China (Nos. U1832183 and 51821001). Shi Huang and Shifeng Luo also would like to acknowledge the financial support from the China Scholarship Council for their PhD study at University of Hull.
Keywords
- Aluminium-Scandium alloy, Synchrotron X-ray total scattering
- Empirical Potential Structure Refinement
- In Operando Study of Solidification
- Liquid Atomic Structure
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys