材料期刊网

利用热力学软件计算了齿轮钢氧含量与夹杂物成分的关系、夹杂物转变条件。结果表明，超低氧20 CrMoH钢中具有较高塑性的非金属夹杂物成分为：SiO2 0%~10%、Al2O3 22%~55%、CaO 42%~60%、MgO 5%~10%，与之平衡的时钢液中铝含量在0.020%左右，钙含量>0.7×10-6，氧含量在0.0005%左右；选择组成为CaO>40%、Al2O3≤37%、MgO10%、(%CaO+%MgO)/%SiO2为10、SiO2含量尽量低的渣系，钢中Al2O3、MgO•Al2O3夹杂物可转变为低熔点的钙铝酸盐。上述结果在工业试验中得到了验证。

Interrelations between oxygen content of gear steel and non-metallic inclusions, and transformations conditions for non-metallic inclusions were calculated using the thermodynamic calculation software Factsage. It is found that the components of non-metallic inclusions with higher plasticity in ultra-low-oxygen gear steel should be composed by SiO2 0%~10%, Al2O3 22%~55%, CaO 42%~60%, and MgO 5%~10%, aluminum content would being about 0.020%, calcium content would being more than 0.7×10-6, and oxygen content would being about 0.0005% in molten steel when the reaction between the inclusion and liquid steel arrived in equilibrium. If the compositions of fining slag with CaO>40%, Al2O3≤37%，MgO10%，(%CaO +% MgO)/%SiO2=10, and SiO2 content as low as possible were selected, Al2O3 and MgO • Al2O3 in molten steel can transform into calcium aluminates with low melting point. The results above have been verified in industrial trials.