About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Local Ordering in Materials and Its Impacts on Mechanical Behaviors, Radiation Damage, and Corrosion
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Presentation Title |
Tuning the Interplay between Local Chemical Order with Lattice Distortion in Planar Slip Bands to Increase Strain Hardening and Ductility in HEAs |
Author(s) |
Evan Ma |
On-Site Speaker (Planned) |
Evan Ma |
Abstract Scope |
When planar slip bands (PSBs) concentrate strains, as often happening in bcc HEAs that have been strengthened by LCOs, the interplay of the latter with the lattice distortion in PSBs offers a way out towards strain delocalization. While the destruction of LCO causes glide plane softening, leading to PSBs, the proliferation of such bands can spread the plastic flow. We carefully crafted a Ti50Zr18Nb15V12Al5 HEA, in which Zr and Al favor LCO, offsetting the lattice strains caused by each. Upon deformation the LCO dissociates, the Zr and Al atoms eventually separate to large enough distance, producing lattice expansion and contraction, to contribute to solid solution strengthening that strain hardens the PSB. The resultant prolific higher-generation PSBs give rise to a 25% uniform tensile ductility and 50% total elongation to failure, both comparable with ductile Nb (at ~10 times its strength). See L Wang et al., Nature Materials 2023. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Characterization, High-Entropy Alloys |