Three Dimensional Evaluations of REM Clusters in Stainless Steel
2014 (English)In: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 54, no 6, 1266-1273 p.Article in journal (Refereed) Published
It is known that clusters in liquid steel have a harmful effect on the casting process and the quality of the final steel product. In this study, clusters. of rare earth metals (REM) were investigated in steel samples of a S30185 stainless steel grade from a pilot trial (PT, 250 kg) and from an industrial heat (IH, 100 t). Samples were taken from the liquid steel at different holding times after the addition of mischmetal. Thereafter, REM clusters collected on film filters after electrolytic extraction and filtration were investigated in three dimensions (3D) by SEM in combination with EDS. The morphology, composition, number and size of clusters in PT and IH steel samples were analyzed and compared as a function of holding time. It was found that typical clusters with regular and irregular inclusions were the main type of clusters (69%-98%) in all PT and IH steel samples. The composition of inclusions in clusters corresponded mostly to REM-oxides. The size of clusters that were observed in different samples varied mainly from 2 to 23 mu m. In addition, the size and number of most clusters in PT are larger than those in IH samples. Furthermore, the formation mechanisms and evolution of different type of REM clusters were discussed in both PT and IH heats.
Place, publisher, year, edition, pages
2014. Vol. 54, no 6, 1266-1273 p.
stainless steel, REM clusters, electrolytic extraction, cluster size distribution
Materials Engineering Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-145670DOI: 10.2355/isijinternational.54.1266ISI: 000337984000013ScopusID: 2-s2.0-84904977580OAI: oai:DiVA.org:kth-145670DiVA: diva2:719509
QC 20140808. Updated from manuscript to article in journal.2014-05-262014-05-262014-08-08Bibliographically approved