About this Abstract |
Meeting |
2016 TMS Annual Meeting & Exhibition
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Symposium
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Characterization of Minerals, Metals, and Materials
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Presentation Title |
Methodology for Determining Spall Damage Mode Preference in Shocked FCC Polycrystalline Metals from 3-D X-Ray Tomography Data |
Author(s) |
, Quan Pham, Pedro Peralta, Brian M. Patterson, Juan P. Escobedo-Diaz, Sheng-Nian Luo, Darcie Dennis-Koller, Ellen K Cerreta, Darrin Byler, Aaron Koskelo, Xianghui Xiao |
On-Site Speaker (Planned) |
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Abstract Scope |
Three-dimensional X-ray tomography (XRT) provides a non-destructive technique to determine the location, size, and shape of spall damage within shock loaded metals. Polycrystalline copper samples of varying thermomechanical histories were shocked via plate impacts at low pressures to ensure incipient spall conditions. Additionally, samples of similar heat-treated microstructures were impacted at various loading rates. All 3-D XRT volumetric void data underwent smoothing, segmentation, thresholding, and volumetric sieves. The inertia tensor was then found for each void, which was used to create best fit ellipsoids correlating shape to damage modes. Density distributions were plotted for the best-fit ellipsoid semi-axes aspect ratios a/c and b/c, where, a≤b≤c. It was found that >60% of voids in heat-treated samples resembled transgranular damage, whereas >70% of voids in the rolled sample resembled intergranular damage. Preliminary analysis clearly indicates an increase of void coalescence with decreasing tensile loading stress rates for impacted samples of similar microstructures. |
Proceedings Inclusion? |
Planned: A print-only volume |