Abstract: To further optimize the explosive spalling resistance and thermal shock resistance of corundum-spinel castables,a composite corundum-spinel castable was prepared using white fused corundum,composite sintered corundum,reactive alumina micropowder,90# alumina-rich spinel micropowder,70# spinel fine powder,and calcium aluminate cement as raw materials.A conventional corundum-spinel castable was also prepared for reference.The composition and microstructure of the spent fast-baking and explosive-spalling-resistant composite corundum-spinel castable were analyzed.The results show that during service,its degradation is mainly caused by the reactions with slag and molten steel,and the damage modes are predominantly slag corrosion,penetration,and structural spalling.By adjusting the matrix composition and microstructure and introducing composite sintered corundum,the strength of the cured castable was significantly improved,and its explosive spalling resistance and thermal shock resistance were enhanced.When applied in a domestic 300 t refining ladle,under relatively low ambient curing temperature conditions,it can meet the demands of short curing time and fast heating.Compared with the conventional corundum-spinel castable,its service life was increased by 60%.

Key words: composite corundum-spinel, composite sintered corundum, ladle working lining, corrosion mechanism, microstructure

摘要： 为了进一步优化刚玉-尖晶石浇注料的抗爆裂性能和抗热震性能,以电熔白刚玉、复相烧结刚玉、活性氧化铝微粉、90#富铝尖晶石微粉、70#尖晶石细粉、铝酸钙水泥为原料,制备了复相刚玉-尖晶石浇注料,同时制备了普遍刚玉-尖晶石浇注料作为对比,并对用后的快烘防爆型复相刚玉-尖晶石浇注料的组成和结构进行了分析。结果表明:服役过程中,复相刚玉-尖晶石浇注料的损毁主要由渣和钢液与耐火材料的反应引起,损毁形式以熔渣侵蚀、渗透和结构剥落为主,通过调整基质组成和结构及引入复相烧结刚玉,显著提高了浇注料的养护强度,改善了抗爆裂性能和抗热震性能。在国内300 t精炼钢包中服役,其在较低的环境养护温度条件下,能够满足短养护时间和快烘烤的需求,与普通刚玉-尖晶石浇注料相比,其使用寿命提高了60%。

关键词: 复相刚玉-尖晶石, 复相烧结刚玉, 钢包工作衬, 侵蚀机制, 显微结构