研究C元素对TiAl基合金(Ti-45Al-3Fe-2Mo)显微组织的影响。随着C元素含量的增加,合金中β相含量的比例降低,而片层晶团尺寸增大。当C含量增加至0.3%和0.5%时,片层间距从267 nm降低至237 nm和155nm,但是进一步增加C含量,片层间距长大至230 nm。这是由C原子的抑制作用及碳化物的析出引起的。800℃时效可以使P-型碳化物析出。随着时效时间的延长,该碳化物主要在晶界处及位错线附近析出并长大,并在不同的入射角(TEM)下有不同的形貌。对其显微组织的变化进行了详细的分析及探讨。 The effect of C element on the microstructure of TiAl-based alloy (Ti-45Al-3Fe-2Mo) was studied. With the increase of C content, the proportion of β phase content in the alloy decreases, while the size of lamellae increases. When the C content increased to 0.3% and 0.5%, the interlamellar spacing decreased from 267 nm to 237 nm and 155 nm, but with a further increase in C content, the interlamellar spacing increased to 230 nm. This is caused by the inhibition of C atoms and the precipitation of carbides. 800 ℃ aging can make P-type carbide precipitation. As the aging time prolongs, the carbides mainly precipitate and grow near grain boundaries and dislocation lines, and have different morphologies under different incident angles (TEM). The microstructure changes were analyzed and discussed in detail.