Interfacial Evolution And Friction And Wear Properties Of Carbon Nanostructured Films

Carbon film has attracted increasing attention due to the superior mechanical,elastic recovery and tribological properties.The factors affecting the friction behavior of carbon nanostructure films mainly include film intrinsic characteristics and external stimulis.This paper discusses the following three aspects:a)The influence of deposition time on the microstructure and tribological properties of DLC films,b)The friction and wear properties of double-sliding surfaces coated with FL-C:H films under ambient humidity,c)Friction driven reduced graphene oxide interface ordering.The interfacial evolution and tribological properties of carbon nanostructured films such as FL-C:H structures and reduced graphene oxides were systematically evaluated.Themain contents and results are shown as follows:AdoptHigh-frequencypulsedplasmaenhancedchemicalvapor deposition?PECVD?and in-situ nitriding technology.Breaking the previous investigation of the friction behavior of single-sided film,the tribology study of the double-sided film film of the friction pairswas realized.The results show that the films deposited for 180 min exhibits super-low friction?⁰.009?and superlong wear life?⁵3,000 cycles?.The influences of deposition time on the composition of the thin films were investigated.It has been found that as the deposition time increases,the carbon film structure transitions from a graphite-like structure to a fullerene-like carbon structure.Simultaneously,the mechanism of the transition during the deposition of the carbon film structure was investigated.The fullerene-like hydrogenated carbon?FL-C:H?films were prepared on Si₃N₄balls and Si substrates by plasma enhanced chemical vapor deposition?PECVD?with methane gas in our laboratory.The friction and wear properties of the friction pair coated by the double sliding surface coated with the fullerene-like structural film strongly depend on the relative humidity?RH?.After tribological experiments under different RH,the COF of the film increased significantly with the increase of RH.When the RH increases,the amount of wear of the FL-C:H films?F-Si?on the silicon wafer also increases.Unlike the F-Si film,the wear of the FL-C:H?F-Si₃N₄?film on the Si₃N₄ ball slightly increases below 70%relative humidity,but increases sharply when it exceeds 70%.The XPS spectrum of the wear scar shows that tribo-oxidation is prone to occur in a humid atmosphere,which c an be explained by a tribochemical reaction closely related to water molecules.And Raman spectra show that the FL-C:H films exhibit high graphitization after friction under high humidity conditions.The friction and wear properties of graphite and r-GO were comparatively studied,and the internal structure evolution of the friction-transfer film formed at the sliding interface was revealed.In the changing load friction process,the COF and wear volume of r-GO has been reduced by 3-7 times and 3-5 times,respectively,when sliding against Al₂O₃ with r-GO powders as solid lubricants.Using a combination with Raman spectra and high resolution transmission electron microscopy,the difference is due to the structure ordering evolution of r-GO.