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DOE OSTI · 2588763

Tracking Dendritic Growth in Hydrogen-Based Hematite Reduction via Computer Vision

Meier, Maycon [Arizona State University]·Mohanta, Ram [Arizona State University]·Korobeinikov, Yuri [Arizona State University]·Leick, Noemi [National Renewable Energy Lab., Golden, CO (United States)]·Sitaraman, Hariswaran [National Renewable Energy Lab., Golden, CO (United States)]·Sridhar, Seetharaman [Arizona State University]·Ankit, Kumar [Arizona State University]
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Abstract

The reduction of hematite to metallic iron using hydrogen (H2) as a reducing agent presents a promising pathway for decarbonizing steel production. In this study, we employ a combination of in situ confocal scanning laser microscopy (CSLM) and advanced computer vision techniques to quantitatively analyze dendritic growth of ferrite during H2-based reduction of iron oxide at high temperatures. A workflow integrating Watershed Image Segmentation (WIS) and Lucas-Kanade Optical Flow (LKOF) is developed to extract both global and local kinetic information from time-resolved micrograph sequences. H2 reduction experiments conducted at 1400 degrees C and 1500 degrees C demonstrate a clear correlation between temperature and reduction rate, as evidenced by accuracy of fitted Johnson-Mehl-Avrami-Kolmogorov (JMAK) parameters. Optical flow analysis further elucidates the anisotropic and branched nature of dendritic growth, providing spatially resolved velocity fields that correlate well with global transformation kinetics. The proposed methodology demonstrates strong agreement with experimental measurements and literature values, offering a robust framework for automated image-based analysis to study kinetics through microstructural evolution in the reduction of iron ore, and likely other reaction-diffusion phenomena.

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08 HYDROGEN97 MATHEMATICS AND COMPUTINGcomputer visiondendrite growthhydrogen reductionwatershed algorithm

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Meier, Maycon [Arizona State University], Mohanta, Ram [Arizona State University], Korobeinikov, Yuri [Arizona State University], Leick, Noemi [National Renewable Energy Lab., Golden, CO (United States)], Sitaraman, Hariswaran [National Renewable Energy Lab., Golden, CO (United States)], Sridhar, Seetharaman [Arizona State University], Ankit, Kumar [Arizona State University]. 2025-08-25. Tracking Dendritic Growth in Hydrogen-Based Hematite Reduction via Computer Vision. https://doi.org/10.1016/j.matchar.2025.115493

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