MgO-MA-Al材料MgO致密层的形成及其抗渣性

Formation of MgO dense layer and slag resistance of MgO-MA-Al materials

以电熔镁砂、电熔尖晶石和金属铝为原料,酚醛树脂为结合剂,制成MgO-MA和含有5%(w)金属Al的MgO-MA-Al试样。在110℃干燥24 h后,一部分试样在密闭匣钵中于1 600℃保温5 h热处理,分析其物相组成和显微结构;另一部分试样于氮气气氛1 600℃保温5 h进行抗钢渣试验。结果表明:1)在密闭匣钵于1 600℃保温5 h热处理过程中,含有5%(w)金属Al的MgO-MA-Al试样因强还原性单质Al的存在促进了MgO向Mg(g)转化,从而促进MgO致密层的形成。2)在氮气气氛1 600℃保温5 h进行抗渣试验的过程中,同样会发生试样外层致密化的过程。这使试样的抗渣渗透性和抗渣侵蚀性得到提高。

MgO-MA samples and MgO-MA-Al samples containing 5 mass%metal Al were prepared using fused magnesia,fused spinel and aluminum as raw materials and phenolic resin as the binder.After drying at 110℃for 24 h,some samples were heat treated in a closed sagger at 1600℃for 5 h to analyze their phase composition and microstructure;the other samples were tested for slag resistance at 1600℃in nitrogen atmosphere for 5 h.The results show that(1)a MgO dense layer is formed on the MgO-MA-Al sample containing 5 mass%Al since the strong reducing Al promotes the transformation of MgO to Mg gas during the heat treatment in the closed sagger at 1600℃for 5 h under nitrogen atmosphere;(2)in the process of the slag resistance test at 1600℃for 5 h in nitrogen atmosphere,the outer layer of the sample is also densified,which improves the slag penetration resistance and the slag corrosion resistance of the samples.