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arXiv · 2304.03740

Three-dimensional morphology of an ultrafine Al-Si eutectic produced via laser rapid solidification

Xinyi Zhou·Paul Chao·Luke Sloan·Huai-Hsun Lien·Allen H. Hunter·Amit Misra·Ashwin J. Shahani
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Abstract

Al-Si alloys processed by laser rapid solidification yield eutectic microstructures with ultrafine and interconnected fibers. Such fibrous structures have long been thought to bear resemblance to those formed in impurity-doped alloys upon conventional casting. Here, we show that any similarity is purely superficial. By harnessing high-throughput characterization and computer vision techniques, we perform a three-dimensional analysis of the branching behavior of the ultrafine eutectic and compare it against an impurity-modified eutectic as well as a random fractal (as a benchmark). Differences in the branching statistics point to different microstructural origins of the impurity- and quench-modified eutectic. Our quantitative approach is not limited to the data presented here but can be used to extract abstract information from other volumetric datasets, without customization.

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Xinyi Zhou, Paul Chao, Luke Sloan, Huai-Hsun Lien, Allen H. Hunter, Amit Misra, Ashwin J. Shahani. 2023-04-07. Three-dimensional morphology of an ultrafine Al-Si eutectic produced via laser rapid solidification. https://doi.org/10.1016/j.scriptamat.2023.115471

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