Substrate influence on the mechanical properties of TiC/a-C coatings

A new experimental approach of TiC/a-C coatings critical relative indentation depth determination is presented. The data comparison of similar coatings obtained by magnetron sputtering on WC-based and stainless steel substrates shows that TiC/a-C nanohardness is affected by the substrate at indentation depths larger than 10-13 % of the coating.s thickness. As for the friction coefficient, the soft substrate influences TiC/a-C coatings at the depths as small as 1 % of the coatings. thickness so this mechanical property is always influenced by the substrate.