ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The novel frictional properties of hydrogenated DLC (Diamond-like Carbon) films havebeen reported for nearly ten years. But up to now, researchers still haven’t known the exactmechanism resulting in the super-low frictional performance of hydrogenated DLC films. Especiallythey have little knowledge on the molecular configuration and structural properties of these kinds offilms. In this paper, CH3 radicals with different impact energies are selected as source species todeposit DLC films on diamond (100) by molecular dynamics simulation. Results show hydrogenatedDLC films can be successfully obtained when impact energy is in an appropriate scope that is no lessthan 20eV. The depositing processes involve impinging diamond surface and bonding procedure.Some atoms, instead of bonding with substrate atoms, fly away from the diamond surface. Onlysuitable impact energy can improve the growth of the film. Within 30eV to 60eV, the maximumdeposition ratio is attained. In addition, when carbon atoms act as the deposition sources, thedeposition ratio is relatively higher. Furthermore, the authors find that species with higherconcentration of carbon atoms in deposition sources lead to a better deposition rate. Carbon atoms aremore reactive than hydrogen atoms. Then the relative densities of DLC films are calculated. Thedensity curves indicate that the structures of the films vary obviously as the impact energy augments.The average relative density is generally monotone increase with the increment of impact energy. Thehybridization of carbon atoms greatly affects the properties of hydrogenated DLC films. Thetransition between sp2 and sp3 will result in the graphitization and reduce the frictional coefficientwhen DLC films are used as tribo-pair in friction
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/57/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.373-374.108.pdf
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