Abstract: Effects of different Al contents(12.3%~25.4%,atomic fraction) on combustion synthesis of Ti₃AlC₂ powders were studied by using Ti,Al,C and TiC powders as raw materials in the Ti-Al-C system when the molar ratio of Ti/C was equal to 3∶2.The formation mechanism of Ti₃AlC₂ was investigated for different Al contents in the raw materials.The experiment results show that the phase formation of combustion synthesized Ti₃AlC₂ is affected greatly by the Al content in the raw materials.The amount of Ti₃AlC₂ in combustion products firstly increases with increasing Al content(12.3%~19.4%), and then decreases with continuously increasing amount of Al(20.6%~25.4%).