About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Advanced Characterization Techniques for Quantifying and Modeling Deformation
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Presentation Title |
Imaging Real-time Plasticity Onset and Single Twinning Events within a Bulk Polycrystalline Magnesium Alloy |
Author(s) |
Matthew Robert Barnett, Jun Wang, Sitarama R. Kada, Andrew Stevenson, Chris Hall, Peter A. Lynch |
On-Site Speaker (Planned) |
Matthew Robert Barnett |
Abstract Scope |
The present work reports a Synchrotron X-ray Laue diffraction technique to probe the grain-level dynamic response of a polycrystalline magnesium alloy. The technique is a “one-shot” approach, which avoids the time-consuming aspects of data acquisition based on stage rotation or sample raster scanning. An in-situ tensile experiment was conducted at IMBL beamline at the Australian Synchrotron using polychromatic radiation in a highly collimated beam 200 ìm in diameter. We focus on the onset of plastic yielding and closely monitor Laue diffraction peak position and intensity. Despite the smooth nature of the elastic-plastic transition evident in the stress-strain curve, the results show the intermittent nature of plasticity at the grain scale within timesteps of 44 milliseconds. It is also seen that bursts of plasticity are highly coupled across nearby grains. Close inspection of the diffraction patterns suggests the larger strain bursts are due to single {10-12} twinning events. Twin events are seen that are both preceded and followed by a period of peak stasis. The burst of twin induced plasticity can thus be employed to define a twin “birth size”, which we quantify, we believe for the first time. |
Proceedings Inclusion? |
Planned: |