Effect of Impurity Te on the Morphology of Alumina Particles in Molten Iron

Abstract

Surface active elements in liquid steel may affect the morphology of non-metallic particles during deoxidation. The effect of Te on the morphology of alumina particles was therefore studied by adding Te to molten iron before Al deoxidation at 1873 K. Dendritic, spherical, faceted, plate-like and clustered particles were identified in all samples. Te, however, considerably changes the relative frequencies of the morphologies, decreasing the amount of dendritic and spherical particles whereas increasing the amount of faceted and plate-like particles. This effect is closely related with the supersaturation degree, stirring, and Te content. The way Te influences the morphology of the alumina particles and the factors influencing Te effectiveness are discussed.