Meghna Desai https://orcid.org/0000-0002-3018-9735 Thilo Rehren https://orcid.org/0000-0002-9169-1198

Abstract

Pre-industrial crucible steel ingots, produced in both Central and South Asia, are an important class of iron-carbon alloys. Their microstructure reflects their formation from a liquid alloy at a carbon content of 1.0–2.5wt%, which is higher than most mild steels but lower than most cast irons. This article introduces a tool to quantify the carbon content of such alloys based on an operator-supervised image analysis which determines the relative proportions of austenite/pearlite and cementite, respectively, from high-contrast back-scatter electron images of unetched samples. Using examples from a recently discovered hoard of crucible steel ingots in Telangana, south-central India, we demonstrate the capabilities of the tool and test its usefulness. The main benefit is in improving accuracy and precision in metallography-based carbon content determination in such alloys by reducing the uncertainty in area estimation in complex microstructures based on visual impression alone.

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How to Cite
Estimating carbon content in crucible steel using image analysis. (2023). Historical Metallurgy, 54(2), 54-64. https://doi.org/10.54841/hm.664
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Articles

How to Cite

Estimating carbon content in crucible steel using image analysis. (2023). Historical Metallurgy, 54(2), 54-64. https://doi.org/10.54841/hm.664