A Comparison of the Tribology of Tetrahedral Amorphous Carbon and Hydrogenated Amorphous Carbon

The tribology of different DLC coatings is studied through different mechanical and tribological tests like micro-hardness, scratch tests, friction in different oils, dry friction and impact-wear tests. The different tests reveal that hydrogen-free DLC coatings exhibit high hardness and low friction coefficient against steel, in boundary lubrication regime. Unfortunately, the remarkable tribological properties of tetrahedral amorphous carbon (ta-C) coatings are balanced by a low fracture toughness and low endurance behaviour, which affect the durability of coated mechanical components.