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arXiv · 2101.02935

MEMS-based in situ electron-microscopy investigation of rapid solidification and heat treatment on eutectic Al-Cu

Phillip Dumitraschkewitz·Matheus A. Tunes·Cameron R. Quick·Diego Santa Rosa Coradini·Thomas M. Kremmer·Parthiban Ramasamy·Peter J. Uggowitzer·Stefan Pogatscher
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Abstract

The solidification behavior of a eutectic AlCu specimen is investigated via in situ scanning transmission electron microscope (STEM) experiments. Solidification conditions are varied by imposing various cooling conditions via a micro-electro-mechanical system (MEMS) based membrane. The methodology allows the use of material processed by a melting and casting route close to industrial metallurgically fabricated material for in situ STEM solidification studies. Different rapid solidification morphologies could be obtained solely on a single specimen by the demonstrated strategy. Additional post-solidification heat treatments are investigated in terms of observation of spheroidization of lamellas during annealing at elevated temperatures.

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Phillip Dumitraschkewitz, Matheus A. Tunes, Cameron R. Quick, Diego Santa Rosa Coradini, Thomas M. Kremmer, Parthiban Ramasamy, Peter J. Uggowitzer, Stefan Pogatscher. 2022-08-05. MEMS-based in situ electron-microscopy investigation of rapid solidification and heat treatment on eutectic Al-Cu. https://doi.org/10.1016/j.actamat.2022.118225

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