Related Experiment Video
Updated: Nov 2, 2025
12:20
Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers
Published on: October 5, 2013
14.9K
Phase equilibria among η-Fe2Al5 and its higher-ordered phases
Tetsuya Hamada1, Masaya Higashi1, Kodai Niitsu1,2
1Department of Materials Science and Engineering, Kyoto University, Kyoto, Japan.
Science and Technology of Advanced Materials
|June 9, 2021
Summary
This study details complex phase transformations of the eta-Fe2Al5 phase upon cooling, revealing new ordered phases. These findings clarify the intricate phase equilibria in the iron-aluminum system at various temperatures.
Area of Science:
- Materials Science
- Physical Chemistry
- Crystallography
Background:
- The eta (η)-Fe2Al5 phase is a key component in iron-aluminum alloys.
- Previous studies established its high-temperature solubility range but lacked detail on low-temperature behavior.
Purpose of the Study:
- To experimentally determine the phase equilibria of the η-Fe2Al5 phase and its related higher-ordered phases.
- To elucidate the complex phase transformations occurring upon cooling.
Main Methods:
- Experimental determination of phase equilibria.
- Analysis of phase transformations and crystallographic ordering.
Main Results:
- Identified four new ordered phases (η", η"', η", ηm) derived from the η phase.
- Characterized the equilibrium relationships and transformation temperatures for these phases.
- Established specific eutectoid and peritectoid reactions governing phase stability below 415°C.
Conclusions:
- The η-Fe2Al5 phase exhibits complex ordering and transformations upon cooling, leading to new stable phases.
- The established phase equilibria provide a comprehensive understanding of the η-framework structure in iron-aluminum systems.
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