| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
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| Symposium
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Integration between Modeling and Experiments for Crystalline Metals: From Atomistic to Macroscopic Scales IV
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| Presentation Title |
Atomistic Modeling of Twin Size Effect on the Localization of Cyclic Strain and Fatigue Crack Initiation in CrCoNi Medium-entropy Alloy |
| Author(s) |
Veronika Mazanova, Milan Heczko, Mulaine Shih, Connor E Slone, Easo P. George, Jaroslav Polak, Maryam Ghazisaeidi, Michael J Mills |
| On-Site Speaker (Planned) |
Veronika Mazanova |
| Abstract Scope |
Twin boundaries play an important role in the localization of cyclic plastic deformation and the fatigue crack initiation in structural materials. It is revealed that in fatigued CrCoNi alloy, thin deformation twins produced during the initial period of cyclic loading are the preferential sites of early strain localization. Comprehensive experimental workflow designed to extract information from the surface and the bulk of tested material by multi-scale electron microscopy suggests the deterministic role of the twin size. Experiments are complemented by atomistic modeling. Local stress fields associated with the twin boundaries both under tensile and compressive external load are generated and visualized by average-atom CrCoNi EAM potential utilized model. As deformation twinning in FCC alloys is of increasing interest, our work suggests that the effect of the twin thickness and its role in the generation of additional shear stress fields and the plastic strain localization should be taken into the considerations. |