Abstract: In order to improve the thermal shock resistance of zirconia slide plates for slag skimming of converters,zirconia materials were prepared using monoclinic zirconia powder,fused magnesia stabilized zirconia (PMD) as main raw materials and magnesia powder (or magnesium hydroxide) as the stabilizer.The effects of the magnesia powder addition,substitution amount of PMD and stabilizer types on the properties,phase composition and microstructure of zirconia materials were studied.Based on the optimal formulation of 86% monoclinic zirconia powder,14% PMD and 3.12% magnesium hydroxide,the dense zirconia plates with the bulk density of 5.26 g·cm^-3,the apparent porosity of 7.9%,the high m-ZrO₂ content of 75% and excellent thermal shock resistance can be prepared after fine powder granulation,200 MPa high pressure molding and 1 720 ℃ high temperature firing.The developed zirconia plates were embedded in slag skimming slide plates of 150 t and 260 t converters in batches.The average service life reached 25 heats,which was 5 heats higher than before,and there were no accidents such as steel leakage and burning through of the slide plates during service.The zirconia slide plate surface was smooth and complete after offline,without cracks and cold steel adhesion.

Key words: slag skimming of converter, zirconia slide plate, monoclinic zirconia, thermal shock resistance

摘要： 为提高转炉挡渣用氧化锆滑板的抗热震性,以单斜氧化锆粉、电熔镁稳定氧化锆(PMD)为主原料,氧化镁粉(或氢氧化镁)为稳定剂,制备了氧化锆材料,研究了氧化镁粉加入量、PMD替代量、稳定剂种类对材料性能、物相组成和显微结构的影响。结果表明:以质量分数分别为86%的单斜氧化锆粉、14%的PMD、3.12%的氢氧化镁为最佳配比,经细粉造粒、200 MPa高压成型、1 720 ℃高温烧成,可制得体积密度为5.26 g·cm^-3,显气孔率为7.9%,m-ZrO₂含量为75%(w),抗热震性优异的高单斜相致密氧化锆滑板。将研制氧化锆滑板镶嵌于转炉挡渣滑板中,在150和260 t转炉中批量使用,平均服役寿命均达到25炉,较之前提高了5炉,且服役时未出现滑板漏钢、机构烧穿等事故,下线后氧化锆滑板板面光滑、完整,无裂纹和冷钢粘连现象。

关键词: 转炉挡渣, 氧化锆滑板, 单斜氧化锆, 抗热震性