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Updated: Sep 20, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.6K
Atomic Interactions and Order-Disorder Transition in FCC-Type FeCoNiAl1-Ti High-Entropy Alloys
1College of Mechanical and Vehicle Engineering, Hunan University, Changsha 410082, China.
Materials (Basel, Switzerland)
|June 10, 2022
Summary
High-entropy alloys offer strength but suffer embrittlement. This study explores FeCoNiAl-Ti alloys, finding Ti content controls order-disorder transitions, enhancing both strength and ductility.
Area of Science:
- Materials Science
- Computational Materials Science
- Physical Metallurgy
Background:
- Single-phase high-entropy alloys exhibit high strength but are prone to embrittlement.
- Precipitation-hardened high-entropy alloys, particularly those with L12-type ordered intermetallics, demonstrate an improved balance of strength and ductility.
Purpose of the Study:
- To investigate atomic interactions and order-disorder transitions in FeCoNiAl1-Ti high-entropy alloys.
- To establish a relationship between composition, atomic interactions, and phase stability.
- To provide insights for optimizing mechanical properties through controlled transitions.
Main Methods:
- First-principles calculations to determine atomic interactions and stability.
- Thermodynamic simulations, including CALPHAD, to model phase behavior.
- Analysis of order-disorder transition temperatures as a function of titanium content.
Main Results:
- Atomic interactions are influenced by the atomic size of constituent elements.
- L12 binary intermetallics display varied thermodynamic stability, with short-range ordering in the alloy system.
- Order-disorder transition temperatures decrease with increasing titanium content.
Conclusions:
- First-principles and thermodynamic simulations accurately predict order-disorder transition characteristics.
- Compositional control, specifically titanium content, offers a strategy to tune transitions.
- Optimizing these transitions is key to enhancing microstructure and mechanical properties of FeCoNiAl-Ti high-entropy alloys.
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