About this Abstract |
Meeting |
5th International Congress on 3D Materials Science (3DMS 2021)
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Symposium
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5th International Congress on 3D Materials Science (3DMS 2021)
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Presentation Title |
Characterization of Free-growing Dendrites Using 4D X-ray Tomography and Machine Learning |
Author(s) |
Tiberiu Stan, Kate Elder, Xianghui Xiao, Peter Voorhees |
On-Site Speaker (Planned) |
Tiberiu Stan |
Abstract Scope |
When metallic alloys are cooled from the liquid, in almost all cases from castings to additive manufacturing, the metal freezes via the formation of dendrites. Using high temporal and spatial resolution synchrotron 4D x-ray computed tomography (XCT), we present the first in-situ observations of free-growing “hyperbranched” dendrites in Al-Zn. Convolutional neural networks were used to segment the reconstructed datasets, and interface energy anisotropy calculations combined with XCT morphological observations were used to track the crystallographic growth directions of dendrite tips through time. We show that a single dendritic root can have arms with tip morphologies ranging from nearly spherical to highly elliptical. Dendrite fragments are also observed moving both with and against gravity, indicating density changes during growth. The 4D experiments give new information regarding the evolution of dendrite tip curvatures, velocities, crystallography, symmetries, and the interface energy anisotropies of Al alloys.
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Proceedings Inclusion? |
Definite: Other |