The properties of slag are very important in the improvement of steel cleanliness. In particular, the value of %CaO/%Al 2 O 3 ratio, slag basicity, fluidity, and oxygen activity in the slag are considered to affect the steel cleanliness directly. To control these values effectively, the method of deoxidation and slag composition control via additives has been changed. The effect of oxygen content before tapping was investigated. By optimising these factors, the total oxygen content of bearing steel was reduced from 12 to 8 ppm.I&S/17051 Relationship between average life and inclusion content: counts based on total inclusions observed

The chemical structure of the interface formed during MgO growth on Fe͑001͒ is studied by vibration spectroscopy employing a high resolution electron energy loss spectrometer. We find direct, spectroscopic evidence for the formation of FeO layer at the interface that is triggered by the dissociation of oxygen molecule by deposited Mg. Even though the growth conditions of MgO are widely varied, FeO cannot be eradicated at the interface. Hence, we propose that the phase where FeO and MgO coexist at the interface, is an entropically stabilized one in regards to the very small difference between the bond dissociation energy of FeO and that of MgO.