| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
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| Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
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| Presentation Title |
On the Role of Annealing Twin Boundaries in the Cyclic Plastic Strain Localization and the Fatigue Crack Initiation in Equiatomic CrCoNi Medium-entropy Alloy |
| Author(s) |
Veronika Mazanova, Milan Heczko, Connor E Slone, Ivo Kubena, Easo P George, Maryam Ghazisaeidi, Tomas Kruml, Jaroslav Polak, Michael J Mills |
| On-Site Speaker (Planned) |
Veronika Mazanova |
| Abstract Scope |
Equiatomic CrCoNi alloy was cold-rolled and heat-treated to produce a fully recrystallized microstructure with average grain size 25 microns and annealing twin boundary (TB) fraction of 0.3. The alloy with this microstructural state combines good cyclic strength with superior resistance to cyclic plastic deformation. Among the mechanisms leading to the extraordinary performance of CrCoNi, the significant role of the TBs in the fatigue crack initiation and growth is revealed. Three different types of interactions between TBs and bands of localized cyclic slip (PSB) are studied: (1) slip transmission across TBs, (2) localization of the cyclic slip along the twin plane, and (3) PSBs impinging on the TBs. Origins of TB-PSB interactions are studied by correlative microscopy based on electron backscatter diffraction, focused ion beam, and transmission electron microscopy. The significance of different TB/matrix configurations is discussed in relation to the fatigue crack initiation and the overall fatigue resistance. |
| Proceedings Inclusion? |
Planned: |