About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
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Mechanical Behavior at the Nanoscale VII
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Presentation Title |
Amorphous Shear Bands in Crystalline Materials as Drivers of Plasticity |
Author(s) |
Xuanxin Hu, Nuohao Liu, Hongliang Zhang, Izabela Szlufarska |
On-Site Speaker (Planned) |
Xuanxin Hu |
Abstract Scope |
Shear-band formation in crystalline materials is found to either lead to voids nucleation and fracture or act as the primary driver of plasticity. This diverse behavior of shear bands raises important questions, such as (i) when amorphous shear bands will form and (ii) when they lead to ductility instead of fracture. Here, we targeted Al-Sm system where shear bands could switch from ductile to brittle behaviors with varied compositions. Based on a combination of experimental and simulation results, we proposed that a key criterion for shear-band formation without pre-existing defects is the similarity in energies between crystalline and amorphous phases. We also demonstrated that a small density change during phase transformation and lower energy cost for shear-band formation compared to cleavage are critical to enable shear-band plasticity. Our findings provide a potential strategy for design of materials with increased toughness. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Phase Transformations, |