LF渣和ρ-Al_2O_3结合铝镁质浇注料的相互作用

Interaction of LF slag and ρ-Al_2O_3 bonded alumina-magnesia castables

以5～3 mm棕刚玉和3～1、≤1 mm板状刚玉为骨料，以0．074 mm电熔白刚玉、0．088 mm电熔镁砂和0．061 mm尖晶石为细粉，以ρ-Al2O3微粉为结合剂，研究了加入质量分数8％的90尖晶石和加入质量分数7％的97电熔镁砂细粉的铝镁质浇注料常温物理性能、抗LF渣的侵蚀和渗透性能。采用SEM对侵蚀后试样进行了显微结构分析，并利用热力学软件Factsage 6．2对侵蚀过程进行了模拟。结果表明：加入质量分数8％的90尖晶石的铝镁浇注料比加入质量分数7％的97电熔镁砂的铝镁浇注料在各温度处理后的常温强度高，显气孔率低，体积密度大，抗LF渣渗透性能优异。铝镁浇注料中引入较多MgO在高温下大量形成原位尖晶石，易造成较大的体积膨胀，对抗渣渗透性能不利，但有利于吸收渣中FeO、MnO，提高渣的黏度，对抗渣侵蚀性能有利。试验结果与热力学软件模拟结果吻合。

Two batches of alumina-magnesia castables were prepared by using brown corundum （5 -3 mm）and tabular corundum （3-1 and ≤1 mm）as aggregates,fused white alumina （0.074 mm）,fused magnesia （0.088 mm）and spinel powder （0.061 mm）as matrix,ρ-Al2O3 as binder,and adding 8 mass%90 spinel and 7 mass%97 fused magnesia,respectively.Cold physical properties,corrosion and penetra-tion resistance to LF slag of the two castables were compared.Microstructures of the two kinds of corroded specimens were investigated with SEM and the corrosion process was thermodynamically simulated by software Factsage 6.2.The results show that：compared with the castable with 7 mass%97 fused magne-sia,the alumina-magnesia castable containing 8 mass%90 spinel has a higher cold strength,a higher bulk density,a lower apparent porosity,and a better penetration resistance to LF slag at all temperatures;high MgO content in alumina-magnesia castables results in more in-situ formed spinel during firing,expanding the volume,which is not beneficial to slag penetration resistance;but the in-situ formed spinel is advanta-geous to absorbing FeO and MnO from the slag,increasing the viscosity of the slag,which is favorable to enhancing the slag corrosion resistance.The experimental results are in good agreement with the thermo-dynamic simulation results.