Development of oxide inclusions during vacuum degassing process

Abstract

This article sets out to study the development of oxide inclusions during the vacuum degassing process at the ASEA-SKF ladle furnace. During the degassing process, five steel and top slag samples were taken, and their chemical compositions were analysed. All steel samples were further analysed by scanning electron microscopy. It was concluded that the vacuum degassing process was a dynamic process during which spinel and calcium aluminate inclusions were dominant. In addition, it was seen that during this process, the percentage share of calcium aluminates compared with spinels, the Ca weight per cent content of the oxides, the average equivalent circle diameter (ECD) of the oxides and the percentage share of the oxides with bigger ECD were increasing, and the oxides tended to form more round shapes.

Keywords:

• Non-metallic inclusions
• Calcium aluminates
• Spinel
• SEM analysis
• ECD