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采用整体加热法对Ｔｉ、Ｃ和Ａ１三种粉末混合料的压坯进行燃烧反应合成，研究了升温速度及Ａｌ含量对反应过程及反应产物微观形貌和相组成的影响，探讨了在Ａ１基中ＴｉＣ粒子的形成机理。对Ｔｉ－Ｃ－Ａｌ体系反应物进行的差热分析（ＤＴＡ）及对产物进行的Ｘ射线衍射分析（ＸＲＤ）和扫描电镜（ＳＥＭ）观察的结果表明，在热爆反应合成过程中，首先是Ｔｉ与Ａｌ反应形成Ｔｉ与Ａｌ的化合物，放出热量，随后促使Ｔｉ和Ｃ的放热反应发生，合成ＴｉＣ时放出的高热使Ｔｉ与Ａｌ的化合物分解，从而使反应产物中只有ＴｉＣ和Ａｌ两相存在；升温速度及Ａｌ含量只有超过一定值时，该体系才能在较低温度发生热爆反应；体系中Ａｌ含量的增加会使合成ＴｉＣ颗粒尺寸变小，当Ａｌ含量从１０升至５０ｗｔ％时，其粒度范围为５μｍ～０．５μｍ。
The overall heating method was used to synthesize the green compact of Ti, C and A1 powder mixtures. The effects of heating rate and Al content on the reaction process and microstructure and phase composition of the reaction products were investigated. Formation mechanism of TiC particles. Differential thermal analysis (DTA) of Ti-C-Al reactants and X-ray diffraction (XRD) and scanning electron microscopy (SEM) observations of the products showed that during the thermal explosion reaction, Ti reacts with Al to form a compound of Ti and Al, which releases heat and then promotes the exothermic reaction of Ti and C. The high heat released during the synthesis of TiC decomposes the compound of Ti and Al so that only TiC and Al are present in the reaction product When the heating rate and Al content exceed a certain value, the system can undergo thermal explosion reaction at a lower temperature. The increase of Al content in the system will make the size of the synthesized TiC particles smaller. When the Al content is increased from 10 to 50 wt% , The particle size range of 5μm ~ 0.5μm.