Fe-Si droplets associated with graphite on blast furnace coke

Abstract

Fe-Si droplets on the surface of blast furnace (BF) coke from 25 to 50 cm at the tuyere level are mostly composed of Fe₃Si, which has various shapes (round, elongated, and irregular) and penetration degrees into the BF coke matrix. The shapes and penetration degrees may depend on the saturation of molten iron by silicon during interaction with the coke matrix. The droplets are covered by a tiny shell of carbon. Graphite observed inside the droplets can be divided into two categories: well-formed tabular crystals with relatively large size and flakes with structures similar as those in cast iron. The textures of the droplets reflect composition, interaction with the coke matrix, and cooling conditions.

Keywords

metallurgical coke / graphite / iron / blast furnaces

References

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