The chrome-containing corundum castables specimens with different nano-CaCO3 additions (0-1.6 wt%) were prepared using tabular corundum,alumina powder,chrome oxide micropowder (average particle size < 5 μm),calcium aluminate cement (Secar71),commercial nano-CaCO3 (average particle size <100 nm) as main starting materials and FS10 as water reducer. The specimens heat treated at 1 000 ℃ and 1 600 ℃ were characterized in terms of apparent porosity,bulk density,cold and hot strengths,and microstructure. The results show that,when the nano-CaCO3 addition is no more than 1.0 wt%,the apparent porosity of the castables increases with nano-CaCO3 addition increasing,both the cold and hot strengths are enhanced; however,when the nano-CaCO3 addition excesses 1.0 wt%,both the cold and hot strengths go down remarkably with nano-CaCO3 addition increasing; the thermal shock resistance is gradually improved with nano-CaCO3 addition increasing in chosen range.
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