Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Experimental determination of the liquidus in the high basicity region in the Al2O3(25 mass%)-CaO-MgO-SiO2 and Al2O3(35 mass%)-CaO-MgO-SiO2 systems
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Micro-Modelling. (Mikromodellering)
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Micro-Modelling.ORCID iD: 0000-0002-3548-8638
2011 (English)In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 42, no 5, 1008-1016 p.Article in journal (Refereed) Published
Abstract [en]

Liquidus in the Al(2)O(3)(25 mass pct)-CaO-MgO-SiO(2)(<20 mass pct) and Al2O3(35 mass pct)-CaO-MgO-SiO(2)(<20 mass pct) systems were determined experimentally in the high-CaO-containing region at 1873 K (1600 degrees C). For the Al(2)O(3)(35 mass pct)-CaO-MgO-SiO(2)(<20 mass pct) system, liquidus data were also determined for 1773 K (1500 degrees C). The equilibrating and quenching technique with subsequent electron probe microanalyzer (EPMA) microanalysis were employed. Based on the data, liquidus lines were constructed for the 25 and 35 mass pct alumina planes at silica contents generally below 20 mass pct. The current results showed a slightly lower solubility of CaO and a higher solubility of MgO at 1873 K (1600 degrees C) for the 25 mass pct Al(2)O(3) section compared with the existing phase diagram. At 1773 K (1500 degrees C), the result showed a slightly lower solubility of both CaO and MgO in the 35 mass pct Al(2)O(3) section compared with the existing phase diagram. In addition, the activities of MgO, CaO, and Al(2)O(3) were estimated at 1773 K and 1873 K (1500 degrees C and 1600 degrees C) using the phase diagram information.

Place, publisher, year, edition, pages
2011. Vol. 42, no 5, 1008-1016 p.
Keyword [en]
Electron probe micro analyzer, Experimental determination, Liquidus, Liquidus lines, Silica content, Phase behavior, Phase diagrams, Silica, Silicon compounds, Solubility
National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-31125DOI: 10.1007/s11663-011-9530-5ISI: 000297251300009Scopus ID: 2-s2.0-80054926265OAI: oai:DiVA.org:kth-31125DiVA: diva2:402779
Note
QC 20110314. Updated from submitted to published.Available from: 2011-03-09 Created: 2011-03-09 Last updated: 2017-12-11Bibliographically approved
In thesis
1. Some Fundamental Aspects Concerning Secondary Steelmaking
Open this publication in new window or tab >>Some Fundamental Aspects Concerning Secondary Steelmaking
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The present thesis deals with some aspects concerning secondary metallurgy of steel where there is little or very inconsistent information in the literature. More specifically, it is devoted to the studies on high temperature phase equilibria in the Al2O3-CaO-MgO-SiO2 system, the formation of ladle glaze and the thermodynamics of magnesium in liquid iron.

First, the solidification of different slags on MgO based refractories was studied in order to reveal the mechanism behind the formation of “ladle glaze”. The formation of the slag glaze layer was studied by dipping MgO rods, dense or porous, into liquid slags at 1873 K. The rods were thereafter cooled at a predetermined rate. From a later SEM-EDS microscopy, it was found that the initial slag composition had the most profound effect on the phases found in the solidified slag layer. It was found that the type of MgO rod used and cooling speed had a minor impact on the morphology on the solidified samples. In addition, the slags used in the study were equilibrated at 1773 K, 1673 K and 1573 K in order to get an understanding of the equilibrium phases and their relationship during cooling. On the basis of the experimental results, the mechanism regarding entrainment of exogenous inclusions from the refractory lining was also discussed.

Secondly, phase diagram studies in the high basicity region of the Al2O3-CaO-MgO-SiO2 system were performed using the quench technique followed by EPMA analysis. The main focus in the study was to find the liquidus surfaces for MgO and CaO saturation at 1773 and 1873 K. Based on the experimental data, phase diagrams for the 25, 30 and 35 mass percent alumina sections were constructed for silica contents generally less than 20 mass percent.. The results generally agreed very well with previous, well established phase diagrams. In addition, the activities of MgO, CaO and Al2O3 were estimated using the phase diagram information.

At last, the thermodynamics of magnesium in liquid iron at 1823 K were studied. In a pre-study, the thermodynamics of Ag-Mg solutions were studied, necessary for the Fe-Mg system. For the Ag-Mg system, two different experimental techniques were used; the vapor pressure method and the gas equilibration technique. The temperature range of the Ag-Mg study was 1573 to 1823 K. It was found that the excess Gibbs energy of this system can be described quite well with a sub-regular solution model. In the Fe-Mg study, the partition of Mg between liquid iron and liquid silver were studied at 1823 K. Using the results from the pre-study, the activity coefficient of Mg in liquid iron and the self-interaction parameter were determined at 1823 K.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2011. 44 p.
National Category
Materials Engineering
Identifiers
urn:nbn:se:kth:diva-31131 (URN)978-91-7415-901-1 (ISBN)
Public defence
2011-04-01, Sal D2, Lindstedtsvägen 5, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20110314Available from: 2011-03-14 Created: 2011-03-09 Last updated: 2011-03-23Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Sichen, Du

Search in DiVA

By author/editor
Gran, JimmySichen, Du
By organisation
Micro-Modelling
In the same journal
Metallurgical and materials transactions. B, process metallurgy and materials processing science
Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 143 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf