Diamond and DLC for tribological applications

Carbon-based films, as (poly)crystalline diamond and amorphous diamond like carbon (DLC), have attracted great interest from both the industry and scientific community due to their exceptional physical, chemical, biomedical, mechanical and tribological properties.

Tribologically, carbon films provide some of the lowest known friction and wear coefficients without any environmental pollution related to their use. However, the widespread application of carbon films has been hindered by a long-standing problem related to the influence of air humidity on their tribological performances. In DLC systems, for example, both highly positive and negative effects of humidity on the friction coefficients and wear rates have been reported even in the same type of tribological test conditions. This uncontrolled behavior is most likely the result of chemical reactions activated at the buried sliding interface interacting with water molecules.

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Literature

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