【摘要】 以氢化钛、碳化硼和硅粉为原料，在热等静压条件下，通过原位合成，制备性能优良的ＴｉＢ２ＴｉＣＳｉＣ陶瓷复合材料。制得的ＴｉＢ２ＴｉＣＳｉＣ陶瓷复合材料的断裂韧性达７．３ＭＰａ·ｍ１／２。运用ＳＥＭ和ＴＥＭ对陶瓷复合材料的微观结构和组织形貌进行了分析。发现复合材料中ＴｉＢ２，ＳｉＣ和ＴｉＣ晶粒尺寸小于１０μｍ，三者之间的相界面清洁。ＳｉＣ和ＴｉＣ晶粒为不规则多边形；而ＴｉＢ２晶粒为规则条状。ＳＥＭ断口分析发现：较大的晶粒发生穿晶断裂，其余则为沿晶断裂。颗粒增强、裂纹偏转和晶粒拔出是其主要的增韧机制。更多还原

【Abstract】 TiB 2 TiC SiC composite is in situ synthesized with the use of TiH 2, Si and B 4C power blend under hot isostatic pressing. The fracture toughness of the fabricated composite is 7.3 MPa·m 1/2 . The microstructure and morphology of the composite are studied with SEM and TEM. It is shown that the grain sizes of TiB 2, TiC and SiC phases are less than 10 μm, and the interfaces of the three phases are clean. TiC and SiC grains are irregular polygons and TiB 2 grains regular platelets. The SEM analyses of the fractured surfaces suggest that transgranular fracture happened to coarse grains, and intergranular fracture to the rest of grains. Particle reinforcement, crack deflection and particle pullout are the main toughening mechanisms.更多还原