以自合成的微孔CA6-MA颗粒(8 ～5、5～3、3～1 mm)为骨料,以速烧刚玉粉(≤0.074、≤0.043 mm)、α-Al2O3微粉、纯铝酸钙水泥为粉料,经配料、混练、振动成型、养护、烘干后,分别在1 000、1 200、1 400、1 600℃保温3h热处理,检测热处理后试样的永久线变化、显气孔率、体积密度、常温抗折强度、常温耐压强度、热态抗折强度和热导率,并分析其显微结构.结果表明:1)试样在1 600℃热处理后的永久线变化为1.14％,1 600℃热处理后试样的显气孔率为59.84％,体积密度为1.51 g·cm-3,常温抗折强度为2.7 MPa,常温耐压强度为7.3 MPa,1 400℃的热态抗折强度为1.4 MPa,1 000℃的热导率为0.219 W·m-1·K-1；2)1 600℃热处理后试样基质中有大量片状CA6,骨料和基质之间结合很好.%Light weight AI2O3-CaO-MgO castable specimens were prepared using self-developed micro-pored CA6-MA particles(8-5,5-3,3-1 mm) as aggregates,rapid fired corundum powders( ≤0.074 and ≤0.043 mm),alumina micropowders and pure calcium aluminate cement as matrix, batching, mixing, vi-brating-shaping,curing,drying,and heating at 1 000,1 200,1 400,and 1 600 ℃ for 3 h,respectively. The permanent change in dimensions on heating,apparent porosity,bulk density,cold modulus of rupture,cold crushing strength,hot modulus of rupture,and thermal conductivity of the hot treated specimens were tested, and their microstructures were analyzed as well. The results show that: (1) the specimen heated at 1 600 ℃ has permanent change in dimensions of 1.14%, apparent porosity of 59.84% , bulk density of 1.51 g · cm-3,cold modulus of rupture of 2.7 MPa and cold crushing strength of 7. 3 MPa,the hot modulus of rupture at 1 400 ℃ of 1.4 MPa,and the thermal conductivity at 1 000 ℃ of 0.219 W · m-1 · K-1 ;(2)a lot of flake CA6 exists in the matrix of the specimen heated at 1 600 ℃,and the aggregates bond well with the matrix.
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