Studies of the glass/silicon powder coating of the commercial submerged entry nozzles respecting clogging of a rare earth metals (REM) alloyed stainless steel
(English)Manuscript (preprint) (Other academic)
The internal surfaces of modern SENs are coated with a glass/silicon powder layer to prevent the SEN graphite oxidation during pre-heating. The effects of the interaction between the coating layer and the SEN base refractory materials on clogging were studied. The results of the study indicated the penetration of the formed alkaline-rich glaze into the Alumina/graphite base refractory during pre-heating. More specifically, the alkaline-rich glaze reacts with graphite to form carbon monoxide gas. Thereafter, dissociation of CO at the SEN/molten metal interface takes place. This leads to reoxidation of dissolved REM, which form the “In Situ” REM oxides at the interface between the SEN and the molten steel. Also, the interaction of the penetrated glaze with alumina in the SEN base refractory materials leads to a formation of a high-viscous alumina-rich glaze during the SEN pre-heating process. This in turn, creates a very uneven surface at the SEN internal surface. The “In Situ” formation of the REM oxides together with the uneven internal surface of the SEN may facilitate the accumulation of the primary inclusions.
Refractory, SEN, Clogging, REM, Coating, glaze, alkaline
IdentifiersURN: urn:nbn:se:kth:diva-25073OAI: oai:DiVA.org:kth-25073DiVA: diva2:355618
QC 201010072010-10-072010-10-072010-10-08Bibliographically approved