CaO-Al2O3-SiO2系渣中Al2O3含量对铝镁质浇注料侵蚀的影响

摘要：钢中添加适量铝元素可以提高其韧性与耐腐蚀性，但在冶炼过程中会影响炉渣中Al2O3含量而改变其与现行铝镁质浇注料的界面反应，制约钢种冶炼及品质提升。因此，采用静态坩埚法开展铝镁质浇注料的抗CaO-Al2O3-SiO2渣蚀实验，并结合热力学模拟计算探究Al2O3含量（w(CaO)∶w(Al2O3)，C/A）变化对耐火材料渣蚀的影响规律，得到以下结论：随着熔渣中Al2O3含量的增加，铝镁质浇注料与熔渣反应界面越易形成更厚的高熔点隔离层，将耐火材料组分向熔渣中的直接溶解转变为间接溶解，有利于提升铝镁质浇注料的抗侵蚀性；当渣中的Al2O3质量分数在32%左右时，熔渣的侵蚀性总体较弱，但当渣中的Al2O3质量分数不小于36%时，熔渣对铝镁质浇注料产生了严重的渗透性，也易造成材料变质剥落。这为面向含铝钢冶炼用耐火材料的优化设计提供参考。

Effect of Al2O3 content in CaO-Al2O3-SiO2 slag on corrosion resistance of alumina magnesia castable

Abstract： The toughness and erosion resistance of steel can be improved by adding an appropriate amount of aluminum. However it will increase the content of Al2O3 in slag and react with the existing alumina magnesia castable, and affect smelting and quality of steel. Therefore, static crucible method was applied, corrosion experiments of the CaO-Al2O3-SiO2 slags on the alumina magnesia castable were carried out, and the influence of Al2O3 content (w(CaO)∶w(Al2O3), C/A ratio) on slag corrosion resistance was investigated by combining thermodynamic simulation. The following conclusions were obtained: with the increase of Al2O3 content in the slags, the thicker isolation layer with high melting point is easier to form at the reaction interface between alumina magnesia castable and the slags. The direct dissolution of the refractory components into the slags can be changed to indirect dissolution, which is conducive to improving the corrosion resistance of alumina magnesia castable. Nevertheless, when the content of Al2O3 in the slag is about 32 wt.%, the slag corrosion is generally weak, when the content of Al2O3 in the slag is more than 36 wt.%, the slag has serious permeability to the alumina magnesia castable, which is easy to cause the deterioration and spalling of the material. It provides guidance on the optimization and design of the refractories for Al containing steel smelting.