关键词: 铝硅系浇注料, 闭孔珍珠岩, 煤矸石陶粒, 综合性能

Abstract: Lightweight alumina-silica castables were prepared using closed-cell perlite (2-4 mm),open-cell perlite (4-6 mm) and coal gangue ceramsites (≤5 mm) as aggregates,floating beads (0.3-0.5 mm),sinking beads (0.6-0.8 mm),silica micropowder,α-Al₂O₃ micropowder,zirconia and zircon micropowder as fines,and Secar 71 (calcium aluminate cement) cement as the binder.The effects of the coal gangue ceramsites addition (0,6%,12%,18% and 24%,by mass) on the properties of the as-prepared lightweight alumina-silica castables were investigated.The results show that:(1)the addition of coal gangue ceramsites can reduce the sintering shrinkage of the specimens and help to improve the strength and thermal shock resistance;(2)the specimens with the addition of coal gangue ceramsites can produce pores in the matrix of the sintered specimens,which provides enough space for the growth of CA₆ complex solid solution and expands the irregular lamellar structure;(3)with the addition of coal gangue ceramsites increasing,the linear shrinkage of the specimens sintered at 1 000 or 1 200 ℃ firstly reduces and then increases,the bulk density increases and the apparent porosity decreases;the cold compression strength and the thermal shock resistance of the specimens sintered at 1 200 ℃ firstly increase and then decrease.Thus,the optimal addition of coal gangue ceramsites is 18%.

Key words: alumina-silica castables, closed-cell perlite, coal gangue ceramsites, comprehensive performance