About this Abstract |
Meeting |
2023 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 |
The Dynamic Signatures of Strain Bursts in Metals |
Author(s) |
Mostafa Omar, Jaafar A. El-Awady |
On-Site Speaker (Planned) |
Jaafar A. El-Awady |
Abstract Scope |
Comprehensive understanding of deformation in metals is contingent on our knowledge of dislocation dynamics and its intermittent behavior. In-situ micromechanical testing techniques are incapable of resolving spatially and/or temporally overlapping activities. In this work, we extend the use of Acoustic emissions technique (AE) to microscale experiments to investigate avalanches’ features which were elusive from micro-mechanical testing alone. AE technique was concurrently used with in-situ compression for Ni micropillars to study dislocation avalanches with respect to the AE waves they generate. Spectral investigation showed a limited frequency range for the dislocation activities. The high temporal resolution associated with the AE technique made it possible to resolve batches of wavelets within the same strain burst. Hence, avalanches activities correlations between features including pre-shock and after-shock behavior, frequency evolution, energies, and velocities were revealed. In addition, the strain-level and the strain burst size were found to have a significant impact on these features. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Characterization, |