The effect of deposition temperature on the microstructure and mechanical properties of TaC coatings

•Tantalum carbide (TaC) coatings were produced by CVD at different temperatures.•Microstructure and mechanical properties were studied as a function of deposition temperature.•Mechanical properties were affected significantly due to the variation in microstructure.

Tantalum carbide (TaC) coatings were produced on carbon/carbon composites by chemical vapor deposition. The effect of deposition temperature on the structure and mechanical properties were investigated. X-ray diffraction results showed that the coatings exhibited a single phase cubic structure. For the coating produced at 1300 °C, the carbon as a minor impurity phase was detected using Raman spectroscopy. Scanning electron microscopy analysis showed smooth and crack free coatings produced at 1100 °C and 1200 °C. At higher temperature, the hardness and Young׳s modulus were found to be affected due to the (i) presence of carbon as a minor impurity phase and (ii) variation in grain size.