Abstract
In order to investigate the influence of the crucible material on the Si-deoxidation, the following experiments were carried out.
Experiment A; The change of concentration of oxygen, silicon and aluminium in liquid iron in an Al203 crucible after addition of metallic silicon was studied at 1635-C.
Experiment B; The process of the dissolution of the Al203 crucible into liquid iron deoxidized with various amount of silicon was investigated, by rapidly raising the temperature of the melt from 1550°C to 1635°C and by measuring the change of the concentration of oxygen, silicon and aluminium at 1635°C.
The solubility proluct [%Si][%O] 2 at steady state in the experiment A agreed with that in the experiment B, but it varied with the concentration of silicon in liquid iron and there was a maximum at about 0.5% silicon.
It depends also on such an experimental condition as the size of the crucible.
The solubility product is affected not only by the acti ity of Si02 which was asorbed on the inner wall of the crucible after deoxidation, but also on the heterogeneity of absorption and the concentrations of silicon and aluminium in liquid iron and of oxygen adsorbed at the interface between the crucible and the melt.