The Influence of Vacuum Treatment on Inclusion Composition: Laboratory Study
2010 (English)In: High Temperature Materials and Processes, ISSN 0334-6455, Vol. 29, no 3, 189-202 p.Article in journal (Refereed) Published
A series of lab scale trials have been carried out with the aim of investigating the effect of vacuum treatment on inclusion chemistry. A ball bearing steel grade (1.47 wt% Cr, 0.96 wt% C) has been melted in a controlled atmosphere in magnesia and alumina crucibles. A laboratory vacuum furnace, which makes it possible to carry out sampling during vacuum treatment, was used. Samples were taken before and during vacuum treatment. Thereafter, the inclusion compositions in the samples were determined using SEM in combination with EDS. The inclusions found were mainly sulphides containing both manganese and chromium. In addition to these, MgO-Al2O3 oxides were found with varying contents of calcium. Furthermore, a few, calcium sulphides were found. Additionally, it was possible to find a small difference in the average inclusion composition in the samples taken before and during vacuum. More specifically, it was seen that the composition of the inclusions becomes more sulphide-rich during vacuum treatment. The change of average inclusion composition was not as large as suggested from theoretical computations and oxides were found at the same extent during vacuum as before. Another finding was that the inclusions from the trial where an alumina crucible was used contained no magnesia, but that the inclusions contained magnesia when a magnesia crucible was used. Even though the effect of vacuum treatment on the inclusion compositions was found to be small, it was concluded that vacuum treatment could not to be neglected when studying inclusions influenced by top slag/metal reactions.
Place, publisher, year, edition, pages
2010. Vol. 29, no 3, 189-202 p.
Experiment, vacuum, laboratory, inclusions, calcium aluminates
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-8124ISI: 000283965900008ScopusID: 2-s2.0-78149273281OAI: oai:DiVA.org:kth-8124DiVA: diva2:13361
QC 20100709. Uppdaterad från submitted till published (20101210). Tidigare submitted till Steel Research International, med titeln "The Influence of Vacuum Treatment on Inclusion Composition: Part 2: Laboratory Study".2008-03-192008-03-192010-12-10Bibliographically approved