Bidirectional Phase Transformations in Multi-Principal Element Alloys: Mechanisms, Physics, and Mechanical Property
Jiayi Sun1,2, Heqing Li1, Yujie Chen3
1School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW, 2006, Australia.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 19, 2024
Summary
Multi-principal element alloys exhibit dynamic bidirectional phase transformations, crucial for advanced material properties. Understanding these mechanisms aids in designing next-generation high-performance alloys.
Area of Science:
- Materials Science
- Metallurgy
- Solid State Physics
Background:
- Multi-principal element alloys (MPEAs) offer exceptional properties due to complex compositions.
- FeMnCoCrNi-based MPEAs are of significant research interest for their unique plastic mechanisms.
Purpose of the Study:
- To elucidate the physical mechanisms and atomistic pathways of dynamic bidirectional phase transformation in MPEAs.
- To investigate the role of intrinsic material properties and external factors in triggering these transformations.
- To highlight the impact of bidirectional transformation-induced plasticity (B-TRIP) on alloy performance.
Main Methods:
- Review of fundamental physical mechanisms governing phase transformations.
- Analysis of atomistic pathways for FCC to HCP and HCP to FCC transformations.
- Examination of the influence of stacking fault energy and external stimuli (thermodynamic, kinetic).
Main Results:
- Identified dynamic bidirectional phase transformation (FCC↔HCP) as a key mechanism in FeMnCoCrNi-based MPEAs.
- Highlighted the critical role of negative stacking fault energy and external factors in enabling B-TRIP.
- Demonstrated the significant influence of B-TRIP on mechanical properties and microstructure development.
Conclusions:
- The B-TRIP mechanism is pivotal for harnessing superior material characteristics in MPEAs.
- Further research is needed to overcome challenges and advance B-TRIP for next-generation alloy design.
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