中文摘要：

以3TiO2＋3C＋（4＋x）Al反应体系为对象，利用电场的激活作用和燃烧合成过程中形成的液态Al对合成产物的渗透作用，探讨了在无外加机械压力的条件下直接燃烧合成致密TiC—Al2O3—Al复合材料的可能性。结果表明，外加电场可提高体系的绝热燃烧温度，从而突破该体系只能在x〈10mol下发生燃烧合成反应的热力学限制；而且，随着体系中过余Al量X的增加，合成的TiC和Al2O3晶粒尺寸减小，合成材料的致密性提高。当体系中过余Al量x=14mol、E=25V／cm时，直接燃烧合成了致密性达92．5％的TiC—Al2O3—Al复合材料，且该材料具有如下力学性能：硬度HRC=56．5，抗弯强度σf=531MPa，断裂韧性K1C=10．96MPa·m^1/2。

英文摘要：

By taking 3TiO2 ＋ 3C ＋ （4＋x） Al as a reaction system, the feasibility was discussed that a dense TiC-Al2O3-Al composite is fabricated directly by using an electric field activated combustion synthesis process and the penetration of molten Al formed during the process into the synthesized products. The results show that the imposition of an electric field can improve the adiabatic combustion temperature of the reaction system, therefore, can induce its self-sustaining combustion synthesis process. Moreover, with increasing of excess Al content, x, the grain size of the in-situ synthesized TiC and Al2O3 particles is decreased gradually. As a result, the density of the synthesized composite is improved significantly. In the case of the excess AI content x = 14mol in the system and the electric field strength E = 25V/cm, a dense TiC-Al2O3-Al composite with relative density of 92.5% has been successfully prepared. The hardness, bending strength and fracture toughness of the synthesized TiC-Al2O3-Al composite are 56.5, 531 MPa, and 10.96 MPa·m^1/2, respectively.