Abstract:The analysis and calculation to the formation mechanism and producing thermodynamics of magnesia-alumina spinel in refining process of ultra-low oxygen experimental steel shows that magnesia-alumina spinel can be formed when the contents of w((MgO)) exceeds 17% in MgO-Al2O3 binary system in 1873K, and the Al2O3 inclusions can transform to magnesia-alumina spinel in front of middle period of LF refining when the aluminium deoxidation molten steel is refined by high basicity and w((CaO))/w((Al2O3))≈1 and strong reducibility top slag in LF refining. The magnesium in molten steel is the medium and bridge of realizing Al2O3 to magnesia-alumina spinel, but the w([Mg]) is controlled by acid-soluble aluminium. Therefore keeping sufficient aluminium in molten steel is the precondition of producing magnesia-alumina spinel. Only more than 1.32×10-7 of w([Mg]) can produce magnesia-alumina spinel when w([Al]) exceeds 0.03% in productive process.
杨俊,王新华. 超低氧冶炼过程镁铝尖晶石形成的热力学分析与控制[J]. 钢铁, 2011, 46(7): 26-31.
YANG Jun,WANG Xin-hua. Thermodynamics Analysis and Control of Formation of Magnesia-Alumina Spinel During Refining of Ultra-Low Oxygen. Iron and Steel, 2011, 46(7): 26-31.