About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Mechanical Response of Materials Investigated Through Novel In-Situ Experiments and Modeling
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Presentation Title |
Deformation and Mechanical Properties of Benzene Microcrystals at Cryogenic Temperatures |
Author(s) |
Wenxin Zhang, Bryce W. Edwards, Lucas L.B. Pabarcius, Lei Zhong, Xuan Zhang, Huajian Gao, Robert Hodyss, Julia R. Greer |
On-Site Speaker (Planned) |
Wenxin Zhang |
Abstract Scope |
Small-molecule organic “minerals” (e.g., benzene, naphthalene) are ubiquitous on cold Solar-System bodies, forming topologies on Saturn’s moon Titan. Understanding its geological history is imperative for designing landed missions and requires knowing the mechanical properties and deformation of organic minerals. We perform in-situ nanomechanical experiments on ~10μm-tall pyramidal benzene crystallites, cryogenically formed from liquid droplets in SEM chamber. TEM analysis reveals single-crystalline microstructure, and micro-compression experiments convey top contact pressure to decay from ~2 GPa at initial contact to ~0.5 GPa at ~1-μm compression. Deformation occurred via layer-by-layer densification of benzene unit cells, evidenced by stiffness signature and stochastic displacement bursts. Molecular dynamics simulations unveiled densification to occur via propagation of intermolecular slip followed by amorphization or phase transition. We demonstrate feasibility of cryogenic in-situ nanomechanical characterization of solid organics, providing direct implications to better understanding geophysics of planetary bodies. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Modeling and Simulation, Characterization |