CaO含量对Al_2O_3-MgO-CaO系浇注料性能的影响

Effect of CaO Content on the Properties of Al_2O_3-MgO-CaO Castable

高纯度的Al_2O_3-MgO-CaO系浇注料正广泛应用于精炼钢包的透气砖、座砖、工作衬及包壁修补料等,纯铝酸钙水泥既是Al_2O_3-MgO-CaO系统浇注料的结合剂,同时又是浇注料中CaO的主要来源。本试验通过改变纯铝酸钙水泥的加入量来改变CaO的含量,探究高温下形成的CA6等矿相对体系性能的影响。结果发现:氧化钙以本研究中的纯铝酸水泥形式引入时,随其引入量的增加,材料经110℃处理后的物理性能呈现优化的趋势;CA6形成产生的体积膨胀在促进结构的致密化的同时,当达到一定程度时,会导致材料结构劣化,因此材料经1550℃处理及5次热循环后,其物理性能呈现先提高后降低的趋势。综合各项性能认为,纯铝酸钙水泥加入量在5wt%~8wt%时其高温强度及抗热震性能较为优异。

High purity A1203-MgO-CaO castables are widely used in purging plug,lining and wall repairing material of the refining ladle.Pure calcium aluminate cement is the binder of castable for A1203-MgO-CaO system,also is the main source of CaO castable.In this experiment,the content of CaO was changed by changing the amount of pure calcium aluminate cement,and the influence of CA6 on the relative properties of the system formed at high temperature was investigated.The results show that the physical properties of the material treated with 110℃showed the trend of optimization with the introduction of the calcium oxide content.The volume expansion of CA6 formed in promoting the densification of the structure,when up to a certain extent,also will lead to deterioration of material structure,so the material is 1550℃and 5 thermal cycles,the physical performance increases at first and then decreases.In summary,the addition of pure calcium aluminate cement at 5wt%-8wt%is superior to its high temperature strength and spalling resistance.