About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Additive Manufacturing of Metals: Applications of Solidification Fundamentals
|
Presentation Title |
The Effect of Solidification Pathway on Grain Boundary Fractality |
Author(s) |
Akane Wakai, Amlan Das, Atieh Moridi |
On-Site Speaker (Planned) |
Akane Wakai |
Abstract Scope |
Austenitic stainless steels 304L and 316L were additive manufactured under the same processing conditions to reveal two distinctive microstructures. The chemical composition, and more specifically the ratio of ferrite-stabilizing constituents to austenite-stabilizing constituents, determines the solidification pathway (ferrite-to-austenite solidification for 304L and primary austenite solidification for 316L). Despite the same processing conditions for both materials, the resulting grain morphology for 304L is particularly unique. There are three aspects to its complex microstructure: (1) the presence of hierarchical grain substructures; (2) there is a wide range of grain size spanning nearly two orders of magnitude; and (3) the grain boundaries are rough and convoluted, resembling a fractal object. The intermediate phase in 304L, ferrite, is responsible for the peculiar grain morphology. Operando X-ray diffraction studies at Cornell High Energy Synchrotron Source substantiate the solidification pathways. The findings from the study open a new avenue for grain boundary engineering using additive manufacturing. |
Proceedings Inclusion? |
Planned: |
Keywords |
Phase Transformations, Iron and Steel, Solidification |