About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Advances in Multi-Principal Elements Alloys X: Structures and Modeling
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Presentation Title |
In-situ 4D-STEM Imaging of the Synergistic Deformation Mechanisms Responsible for the Fracture Resistance in CrCoNi |
Author(s) |
Yang Yang, Sheng Yin, Qin Yu, Ruopeng Zhang, Mark Asta, Robert Ritchie, Andrew Minor |
On-Site Speaker (Planned) |
Yang Yang |
Abstract Scope |
High- and medium-entropy alloys (HEAs and MEAs) have shown excellent fracture toughness, especially under cryogenic temperatures. It was previously shown by in-situ TEM that a synergy of multiple deformation mechanisms including dislocations and twinning is responsible for such outstanding mechanical performance. On the other hand, the existence of chemically local ordering, i.e., short-range-order (SROs), has recently been directly imaged by multiple research groups. However, the interplay between SROs and the mechanical performance in HEAs and MEAs still remains unclear. Here, we applied a new technique, namely in-situ four-dimensional scanning transmission electron microscopy (in-situ 4D-STEM), to study the mechanical deformation in CrCoNi MEA at nanometer resolution in real-time. We directly probed the critical role of SROs on the tuning of nano-structural deformation mechanisms. With further insights from molecular dynamics simulations, our study identified the critical steps in the synergistic deformation mechanisms responsible for the fracture resistance in CrCoNi. |
Proceedings Inclusion? |
Planned: TMS Journal: Metallurgical and Materials Transactions |
Keywords |
Characterization, Mechanical Properties, High-Entropy Alloys |