Microtribological studies of different nanocomposite TiC/a-C:H coatings using a modified nanoindentation setup

The microtribological behavior of different nanocomposite TiC/a-C:H coatings against 100Cr6 (AISI 52100) balls with 250 mum radius has been studied using a modified nanoindentation setup and was compared to the results of macroscopic pin-on-disc ( POD) experiments. First results reveal significant differences between macroscopic friction coefficients mu(POD) determined using POD tests and microscopic friction coefficients mu(micro). On the macroscopic scale low friction coefficients can be obtained for high hardness coatings. On the microscopic scale the high hardness samples induce considerable wear on the steel counter-body leading to high microscopic friction coefficients of around 0.3. For samples with lower hardness no wear has been observed and low microscopic friction coefficients (<0.2) can be achieved.