| 1. |
- Ekengard, Johan, et al.
(författare)
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Theoretical study of equilibrium reactions between metal droplets and slag
- 2007
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Ingår i: Steel Research International. - : Wiley. - 1611-3683. ; 78:2, s. 109-116
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Tidskriftsartikel (refereegranskat)abstract
- The dispersion of metal droplets in slag was investigated through analysis of slag samples taken during ladle refining at Scana Steel in Bjorneborg, Sweden. The chemical composition of steel droplets found in the ladle slag was determined for five industrial-scale heats. Possible reactions occurring between the steel droplets and slag were identified, as were differences in steel-droplet and steel-bulk composition. Three different slag models were used to calculate the activities of oxide components (Al2O3 and SiO2) in the slag. These results were then used in the dilute-solution model, whereby oxygen activities in the steel droplets were calculated and compared with measured oxygen activities in the steel bulk. Significant differences were found in the comparison of both the calculated and measured oxygen activities and the steel bulk and droplet compositions.
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| 2. |
- Steneholm, Karin, et al.
(författare)
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Effect of top slag composition on inclusion characteristics during vacuum degassing of tool steel
- 2007
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Ingår i: Steel Research International. - : Wiley. - 1611-3683. ; 78:7, s. 522-530
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Tidskriftsartikel (refereegranskat)abstract
- The focus of the study was to investigate the effect of the chemical composition of the top slag on the inclusion chemical composition during vacuum treatment of a plastic mould tool steel. Sampling was done before and after vacuum degassing. The chemical composition of the inclusions was determined by using SEM combined with EDX. The results showed that several inclusion compositions were found before vacuum degassing, while only one main composition of inclusions was present after vacuum degassing. Furthermore, the composition of the top slag was found to have a great influence on the composition of the inclusions found in samples taken after vacuum degassing. The present study also shows that the vacuum degassing effectively reduces the number of inclusions in steel. Finally, the thermodynamic calculations of the activities using Wagner's equation were found to predict a lower oxygen activity value than the calculations made using the Thermo-Calc software.
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