Morphology and growth of alumina inclusions in Fe–Al alloys at low oxygen partial pressure

The degree of supersaturation is a factor that influences the Al₂O₃ inclusion characteristics in steel. The influence of the addition of a large amount of Al in the molten steel on the formation, growth and morphology of Al₂O₃ inclusions was investigated by laboratory scale experiments. Consecutive steel samples were taken during the deoxidation process and subjected to chemical analysis (ICP-AES), automated image analysis (AIA) and scanning electron microscopy (SEM) assessment with respect to the extracted inclusions. The characterisation and quantification of Al₂O₃ particles show different growth processes, leading to variations in particle size distribution as well as in the morphology.