About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Materials Processing and Kinetic Phenomena: From Thin Films and Micro/Nano Systems to Advanced Manufacturing
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Presentation Title |
Control of Quasi-periodic Lengthscales and Morphologies in Eutectic Thin Films via Directional Laser Solidification |
Author(s) |
Eli Sullivan, Jerrold A. Floro |
On-Site Speaker (Planned) |
Jerrold A. Floro |
Abstract Scope |
Directional solidification in eutectic alloys forms interdigitated bicrystals with quasi-periodic structure. Periodicities are controlled by the solidification speed and can reach the nanoscale. Thin film eutectic alloys are amenable to directional solidification using low-power laser scanning, subject to constraints around agglomeration, heat flow, and evaporation. Eutectic nanostructures are of interest for studying interfacial scattering and anisotropy in energy transport, and as an alternative schema for nanostructured functional materials. In eutectic Al-Cu thin films, highly-regular, parallel phase lamellae with periodicities below 50 nm are easily obtained. Chaotic lamellar structures featuring tortuous lamellae may occur when composition deviates from the eutectic. Solitary tilt waves, oscillatory instabilities, and extreme lamellar branching events arise due to inherent instabilities associated with the moving solid-liquid interface during hypoeutectic solidification. Additional structural control may be afforded using pre-imposed patterning to direct heat flow, and to instigate instabilities. Support of the NSF under grant DMR-1663085 is gratefully acknowledged. |
Proceedings Inclusion? |
Planned: |
Keywords |
Thin Films and Interfaces, Solidification, Nanotechnology |