C-N/TiN_x nanostructured multilayer coatings have been deposited by reactive sputtering from concurrently operated carbon and titanium targets. The side by side target configuration, where the substrate holder is passing continuously through two sputtering zones, has been used. Mass-flow of nitrogen as well as voltage measurements of sputtering cathodes were used for monitoring and process control. In various stable deposition conditions a large variation in friction of the multilayer coatings was observed. For an Si_3N_4 ballreciprocating on a C-N/TiN_x film, a friction coefficient of 0.1 was measured. In this case the coating was deposited at the flow value, where total pressure shows an abrupt increase. However, a different deposition condition has a friction coefficient close to 0.9 thus flow values are very crucial. For C-N/Tin_x multilayers deposited in pure nitrogen, the friction coefficient was approximately 0.2. The acoustic emission scratch test (LSRH Revetest) was used for the measurement of coating adhesion, but also for characterisation of the nanostructured systems. The deterioration of the indenter diamond will be discussed in context with the acoustic emission signal. The friction coefficient and the film transferred in a reciprocating ball on disk tribometer was measured. Preliminary results on the dynamic impact wear method will be reported. The multilayer concept is very interesting because friction coefficients for conventional titanium carbon nitrides have previously shown fairly high values. An indirect proof for transfer of a possibly, crystalline C-N film to the homologous Si_3N_4 ball will be discussed.
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