摘要
The castables were prepared from spherical lightweight mullite aggregates,bauxite,SiO2 fine powder,α-Al2O3 fine powder and calcium aluminate cement.The performance changes of the castables were studied after heat treatment at 110℃for 24 h,1100℃for 3 h,1200℃for 3 h and 1300℃for 3 h.The results illustrate that the cold modulus of rupture and hot modulus of rupture of the castable increase with the rising heat treatment temperature.The cold crushing strength shows a“V”change trend when the heat treatment temperature rises from 1100 to 1300℃.After the specimen is heat treated at 1300℃,the thermal conductivity is 0.500 W·m-1·K-1,0.586 W·m-1·K-1,0.595 W·m-1·K-1 at 300,600 and 900℃,respectively.The SEM analysis explains the change trends of these properties.The prepared lightweight mullite castables can be applied as the working lining of hot-blast furnaces.
The castables were prepared from spherical lightweight mullite aggregates, bauxite, SiO2 fine powder, α-Al2 O3 fine powder and calcium aluminate cement. The performance changes of the castables were studied after heat treatment at 110 ℃ for 24 h, 1 100 ℃ for 3 h, 1 200 ℃ for 3 h and 1 300 ℃ for 3 h. The results illustrate that the cold modulus of rupture and hot modulus of rupture of the castable increase with the rising heat treatment temperature. The cold crushing strength shows a "V" change trend when the heat treatment temperature rises from 1 100 to 1 300 ℃. After the specimen is heat treated at 1 300 ℃, the thermal conductivity is 0.500 W·m-1·K-1, 0.586 W·m-1·K-1, 0.595 W·m-1·K-1 at 300, 600 and 900 ℃, respectively. The SEM analysis explains the change trends of these properties. The prepared lightweight mullite castables can be applied as the working lining of hot-blast furnaces.
