Mitigating Strain Localization via Stabilized Phase Boundaries for Strengthening Multi-Principal Element Alloys
Jinliang Du1,2,3, Shukuan Guo4, Hangqi Feng1
1School of Naval Architecture, Ocean and Energy Power Engineering, Wuhan University of Technology, Wuhan, 430063, P. R. China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|March 8, 2025
Summary
Researchers developed a novel bioinspired alloy by integrating nanoscale body-centered cubic (BCC) and face-centered cubic (FCC) phases. This multi-principal element alloy (MPEA) achieves ultra-high strength and ductility without heat treatment, overcoming traditional limitations.
Area of Science:
- Materials Science
- Metallurgy
- Mechanical Engineering
Background:
- Multi-principal element alloys (MPEAs) offer stability for additive manufacturing but suffer from strain localization, limiting their mechanical properties.
- Conventional strategies to enhance toughness often focus on either suppressing high-energy sites or dissipating energy at crack tips, rarely achieving both.
Purpose of the Study:
- To introduce nanoscale body-centered cubic (BCC) and face-centered cubic (FCC) phases into MPEAs, inspired by mouse enamel.
- To enhance MPEA toughness and strength by mitigating strain localization through bioinspired microstructural design.
Main Methods:
- Incorporation of nanoscale BCC and FCC phases stabilized at phase boundaries within MPEAs.
- Utilizing atomic calculations to investigate dislocation transfer mechanisms across phases.
- Characterization of mechanical properties, including tensile strength and ductility.
Main Results:
- Achieved ultra-high tensile strength (≈1458.1 MPa) and ductility (≈21.2%) without heat treatment.
- Demonstrated synergistic toughening mechanisms including crack deflection, blocking, and bridging.
- Atomic calculations revealed partial atomic plane migration driving continuous dislocation transfer across phases.
Conclusions:
- The bioinspired MPEA design overcomes local hardening limitations of nanoscale alloys.
- Fundamental mechanical mechanisms in MPEAs were uncovered, advancing the understanding of ultra-strong, ductile materials.
- This approach offers a new pathway for designing high-performance alloys for demanding applications.
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