Due to energy saving and cost reduction aspects for technical applications, the optimisation of tribological systems in wind energy and pneumatic systems is very important to target the industrial needs for highly efficient tribological applications. Besides the development of better tribological active polymers the idea of a functionalisation of existing materials via the usage of e.g. diamond like carbon (DLC) and alternative coatings should be able to support these materials especially for starved lubrication conditions.
In the recent work two different kind of coating technologies were used for the deposition on elastomeric- and carbon fibre materials. First, physical vapour deposition (PVD, magnetron sputtering) was used generating DLC and MoS2 hybrid coatings for thermoplastic polyurethane (TPU), fluoroelastomers (FKM) and nitile butadiene rubber (NBR). Second, chromium nitride based multilayer coatings were deposited on carbon fibre reinforced epoxy composites were applied by sputtering. Both systems were tested under dry and initial lubricated state using rotational (pin on disc) and linear (pin on plate) test configurations with polymeric and metallic based counterparts. Extensive failure analysis (light microscopy and scanning electron microscopy) has been made to locate the different mechanisms based on dry and lubricated states.
The results related to the friction and wear behaviour show that the cohesion strength in the coatings and the adhesion between the coating and the substrate is crucial. Furthermore it was shown that based on the chemical composition and mechanical and physical properties of the substrate material the coating technology has to be individual adapted to material and the targeted application.