中文摘要：

为延长干熄焦炉牛腿部位耐火材料的使用寿命,以莫来石、碳化硅为骨料,碳化硅粉、熔融石英粉、α-Al2O3粉和硅微粉为基质,铝酸钙水泥为结合系统,外加钢纤维制备了干熄焦炉牛腿用莫来石-碳化硅浇注料。研究了钢纤维种类（熔抽弯月型、剪切平直型、压痕波浪型、冷拔端勾型）和添加量（外加体积分数分别为0、1%、2%和3%）对该浇注料性能的影响,同时结合试样的载荷-位移曲线分析了浇注料中钢纤维的增韧机制。结果表明：1）表面粗糙的熔抽弯月型和与基体材料锚固作用强的冷拔端勾型钢纤维增强效果优于剪切平直型和压痕波浪型钢纤维;2）适量的钢纤维不仅对浇注料的力学性能,抗热震性和耐磨性能具有显著的提高,还能减缓裂纹的扩展,使其断裂能提高了49.0%,钢纤维合适的外加体积分数在2%以内;3）钢纤维与浇注料的界面粘结力和机械锚固力是钢纤维增强浇注料的关键因素。

英文摘要：

The mullite-Si C castables for coke dry quenching（ CDQ） furnace corbel pillar were prepared by taking mullite and silicon carbide as aggregates,silicon carbide powder,fused silica powder,α-Al2O3 powder and silica fume as matrix,calcium aluminate cement as binding system,and extra-adding steel fibers to extend the CDQ furnace refractory life. The effects of steel fiber types（ melt pumping meniscus,cut straight type,wavy indentation,cold-drawn hook） and steel fiber extra-contents（ 0,1%,2%,3% by volume） on the properties of mullite- Si C castables were investigated. Then the toughening mechanism of steel fiber in the castables was analyzed according to the load-displacement curves. The results show that：（ 1） the toughening effects of the melt pumping meniscus steel fiber with rough surface and cold-drawn hook steel fiber with strong anchoring effect with the matrix are better than those of cut straight steel fiber and wavy indentation steel fiber;（ 2） the suitable amount of steel fiber（ less than 2%） in mullite- Si C castables not only significantly improves the mechanical properties,thermal shock resistance and wear resistance,but also improves the fracture energy by 49. 0% and slows the crack growth;（ 3） the bond strength and mechanical anchoring force between steel fiber and castable interface are key elements of steel fiber reinforced castables.