Chemical vapor infiltration was applied to deposit TaC thin film on carbon fibers using TaCl(5)-Ar-C(3)H(6)-H(2) source. The influence of temperature, pressure and addition of H(2) on phase composition and morphology of the coating had been studied. The results showed that the composition of the coating changes with temperature. The films are mainly composed of TaC and C when deposited at 800-900 degrees C and C phase disappears at 950 degrees C and 1000 degrees C. TaC grains are very small at 800 degrees C and get bigger at 900 degrees C; while at 1000 degrees C, a dense coating has developed. The influence of pressure on coating composition is much weaker when deposited at 850 degrees C and the films are consisted of TaC and C phases at 0.6-8.0 kPa; TaC grains formed at 0.6 kPa are smaller and more homogeneous than those obtained at 8.0 kPa. With 100 ml/min H(2) flow, the coating composition changes and turns into a mixture of TaC and Ta(2)C with fine and homogeneous grains at 850 degrees C and coarse grains at 950 degrees C. (C) 2008 Elsevier B.V. All rights reserved.