In order to reduce the negative effect of gross Al-rich inclusions on high aluminum steel, both thermodynamic calculations and designed deoxidization experiments were performed in condition of different silicon and al...In order to reduce the negative effect of gross Al-rich inclusions on high aluminum steel, both thermodynamic calculations and designed deoxidization experiments were performed in condition of different silicon and aluminum deoxidization sequences. Thermodynamic calculations demonstrated that the complex inclusions with low melting point (harmless inclusions) are more favorable to be formed in condition that the melt was deoxidized using ferrosilicon first and then pure aluminum (Si/A1 deoxidization) than that deoxidized using pure aluminum first and then ferrosilicon (AI/Si deoxidization). Al-rich inclusion decreases 83% from A1/Si deoxidization to Si/A1 deoxidization. The experimental results showed that the total quantity of inclusions decreases by 24% and the proportion of harmless inclusions is doubled when comparing Si/Al deoxidization with Al/Si deoxidization. The morphology of complex inclusion tends to be spherical, and the mean size is less than 5μm in condition of Si/Al deoxidization. The formation mechanism of harmless inclusions was discussed, and it is believed that the inclusions can be controlled reasonably in high aluminum steel using Si/Al deoxidization.展开更多
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (No. U1460103). Support was also provided by the Instrumental Analysis & Research Center in Shanghai University.
文摘In order to reduce the negative effect of gross Al-rich inclusions on high aluminum steel, both thermodynamic calculations and designed deoxidization experiments were performed in condition of different silicon and aluminum deoxidization sequences. Thermodynamic calculations demonstrated that the complex inclusions with low melting point (harmless inclusions) are more favorable to be formed in condition that the melt was deoxidized using ferrosilicon first and then pure aluminum (Si/A1 deoxidization) than that deoxidized using pure aluminum first and then ferrosilicon (AI/Si deoxidization). Al-rich inclusion decreases 83% from A1/Si deoxidization to Si/A1 deoxidization. The experimental results showed that the total quantity of inclusions decreases by 24% and the proportion of harmless inclusions is doubled when comparing Si/Al deoxidization with Al/Si deoxidization. The morphology of complex inclusion tends to be spherical, and the mean size is less than 5μm in condition of Si/Al deoxidization. The formation mechanism of harmless inclusions was discussed, and it is believed that the inclusions can be controlled reasonably in high aluminum steel using Si/Al deoxidization.