关键词: 转炉挡渣, 氧化锆滑板, 单斜氧化锆, 抗热震性

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