The andalusite composite ceramics was fabricated via pressureless sintering process using andalusite powder as staring material. The effects of the composition of body materials and the sintering temperature on the sintering character and mechanical properties of the samples were also analyzed. Moreover, the composition, microstructure and mechanical properties of the samples were characterized by scanning electron microscope, X-ray diffractometer and universal testing machine, respectively. The results show that the water absorption is 0.41%, the porosity is 1.10%, the bulk density is 2.69 g/cm3, and the bending strength is 128.78MPa, when the samples were ifred at 1490℃for 2 h. After 30 times quenching from 1100°C to room temperature in air cooling, the bending strength increased from 128.78 to 142.55 MPa. The X-ray diffraction peaks suggested fully developed mullite and zircon phases by reaction sintering of andalusite and PSZ. Microstructure consisting of mullite as a continuous predominant phase in which zircon grains were homogeneously distributed improved almost all the mechanical and fracture properties. The andalusite composite ceramics could be one of the most promising materials for high temperature heat pipe.%以红柱石为主要原料，采用无压烧结制备了用于太阳能热发电的红柱石复相陶瓷输热管，研究了组成和烧结温度对材料烧结性能和力学性能的影响。利用X射线衍射仪、扫描电子显微镜以及万能试验机表征了样品的物相组成、微观结构和力学性能。结果表明，在1490℃烧结温度下保温2 h获得了性能优良的红柱石复相陶瓷，样品吸水率为0.41%，气孔率为1.10%，体积密度为2.69 g/cm3，抗折强度达128.78 MPa；经30次抗热震(室温-1100℃，在空气中气冷)测试后，样品的抗折强度为142.55 MPa。XRD、SEM分析结果表明，复相陶瓷的相组成为莫来石、锆英石和α-方石英等，锆英石和α-方石英均布在莫来石的晶粒间，提高了复相陶瓷的机械性能和断裂性能。
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