The magnesium aluminate based crucible specimens with the outer sizes of φ50 mm×40 mm and the inner hole of φ25 mm ×25 mm were prepared using spinel aggregate and fine powder,α-Al2O3mi-cropowder and light calcined MgO micropowder as starting materials,and firing at 1 600 ℃for 5 h in order to develop the suitable refractories to replace high chrome bricks as the coal-water slurry gasifier lining. The corrosion behavior of molten coal slag to the specimens at high temperatures was studied with the static crucible method and by means of XRD,and SEM equipped with EDS.The results show:(1)the cor-roded magnesium aluminate spinel material has a loose structure and obvious cracks,and the molten coal slag completely penetrates into the specimen;(2)the phase composition of spinel material changes after the corrosion of molten coal slag,besides the original magnesium aluminate spinel,a new phase,magnesia hercynite composite spinel,forms;(3)the corrosion of molten coal slag to magnesium aluminate spinel ma-terial is mainly physical infiltration,and then chemical dissolution.%为了实现水煤浆气化炉炉衬材料的无铬化,研究开发合适的耐火材料代替水煤浆气化炉用高铬砖,以尖晶石骨料及细粉、α-Al2O3微粉和轻烧MgO微粉为原料,于1600 ℃保温5 h烧成,制备了φ50 mm×40 mm、内孔为φ25 mm×25 mm的镁铝尖晶石质坩埚试样.采用静态坩埚法,借助XRD、SEM+EDS研究了高温煤熔渣对试样的侵蚀行为.结果表明:1)侵蚀后的镁铝尖晶石材料结构疏松,出现较明显的裂纹,煤熔渣完全渗入试样内部.2)经煤熔渣侵蚀后的镁铝尖晶石材料,物相组成发生变化,除原有的镁铝尖晶石外,还有新物相镁铁铝复合尖晶石相存在.3)煤熔渣对镁铝尖晶石材料的侵蚀机制是物理渗透为主,化学熔蚀为辅.
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