Chromite flour, a finely ground form of chromite ore (composed mainly of chromium iron oxide (FeCr₂O₄)), has several industrial applications due to its high melting point, chemical stability, and refractory properties. Here are its key uses:
1. Refractory Industry
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Foundry Molds & Cores: Chromite flour is used as a facing material in sand molds for metal casting (especially steel) to improve surface finish and prevent metal penetration.
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Refractory Bricks & Linings: Added to magnesia-based bricks for furnaces (e.g., steelmaking ladles, cement kilns) to enhance thermal shock resistance and corrosion stability.
2. Welding Fluxes
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Acts as a slag conditioner in submerged arc welding (SAW) fluxes, improving arc stability and weld quality.
3. Ceramics & Glass Production
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Used as a colorant (green/black hues) in glass and ceramics.
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Provides high-temperature stability in kiln furniture (e.g., saggers).
4. Chemical Industry
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A precursor for chromium chemicals (e.g., sodium dichromate) after processing.
5. Specialized Coatings
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Applied in high-temperature coatings for aerospace and industrial equipment.
6. Geotechnical & Construction
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Occasionally used in heavy concrete for radiation shielding or as an aggregate in high-density applications.
Key Properties Driving Use:
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High melting point (~2,180°C)
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Resistance to thermal shock and slag corrosion
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Inertness in oxidizing/reducing environments
