The application of Si Al Fe alloy deoxidization is proved to be effective by practical application. Compared with aluminium deoxidization, the yield of aluminium is high, the residual aluminium content is easy to control, and the inclusion morphology is improved.
The main reason for the high element yield is that the specific gravity of the alloy is 2.7 g/cm 3, the specific gravity of ferrosilicon aluminum (FeAl30Si20) is 3.5-4.2 g/cm 3, and the specific gravity of the final slag is generally 2.8-3.2 g/cm 3. Therefore, the oxygen reaction between aluminum and air and slag is effectively controlled.
It is generally believed that complex deoxidization products are formed and the activity of oxides decreases, which is conducive to the deoxidization reaction. In addition, it is easy to generate low melting phase, which makes the inclusions easy to polymerize and promote the removal of floatation. The total aluminium content in steel is higher in the former than in the latter, but higher in the acid-soluble aluminium in the latter than in the former when aluminium and ferrosilicon (FeAl30Si20) are extracted and deoxidized respectively. This shows that the inclusions of aluminium oxides are greatly reduced when ferrosilicon is used.