An Experimental and Thermodynamic Study of Non-Metallic Inclusions in High Si Stainless Steels Regarding Clogging During Casting
2014 (English)In: Steel Research International, ISSN 1611-3683, Vol. 85, no 10, 1410-1417 p.Article in journal (Refereed) Published
Clogging of high Si-containing stainless steel grades was studied by metallographic examinations of steel samples from clogged and non-clogged heats as well as by thermodynamic modeling using Thermo-Calc and FactSage. Morphology, composition, number and size of inclusions and clusters in the steel samples were determined on a polished surface of the steel samples by using a scanning electron microscope equipped with energy-dispersive X-ray spectrometer. The results showed that the content of Al in ferroalloys added during ladle treatment should be controlled to avoid a formation of spinel MgO-Al2O3 inclusions in liquid steel and a resulting clogging during casting. The thermodynamic calculations showed that the Al content in a melt during ladle treatment and casting should not be larger than 0.003% to obtain < 1% of MgO-Al2O3 inclusions in the liquid steel for a 1.9% silicon content. Moreover, calculations also showed that if the Si content increased from 1.9% (non-clogging heats) to 2.65% (clogging heats), the number of MgO-Al2O3 inclusions decreased slightly. Moreover, it was found that an increased amount of FeSi additions for correction of Si content in the melt increase the Al content. As a result, the number of spinels and clusters increases, which is the primary cause for clogging during casting of these steel grades.
Place, publisher, year, edition, pages
2014. Vol. 85, no 10, 1410-1417 p.
high Si stainless steel, clogging, non-metallic inclusion, spinel, thermodynamic calculation
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-155472DOI: 10.1002/srin.201300368ISI: 000342808000001ScopusID: 2-s2.0-84908093828OAI: oai:DiVA.org:kth-155472DiVA: diva2:762536
QC 201411122014-11-122014-11-062014-11-12Bibliographically approved