Preparation, Characterization and Performance of Metal Containing Diamond-Like Carbon Multilayer Film Nanostructures
| Autor: | Jui-Yun Jao, 饒瑞昀 |
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| Rok vydání: | 2012 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 100 The study of synthesis of metal containing diamond-like carbon (Me-DLC, Me=Cr/Cu, Ti/Cu, Ti/Cu) multilayers thin films and their subsequent characterisation are the goals of this thesis. An important disadvantage shown by DLC films is their high intrinsic stress, which limits their adherence to substrate if their thickness approaches 1 μm. The proposed solutions are the deposition of a metallic buffer layer, the preparation of graded films and multilayer structures. The DLC films containing various metal doping were synthesized by using a cathodic arc deposition (CAD) process. The Me-DLC thin films deposition used the mixture of C2H2 gases atmosphere with the Ti or Cr and Cu metal as cathodic materials. The composite film structure consists of a Me-DLC multilayers film on top of a graded metal nitride interlayer, which provides enhanced mechanical and tribological properties. This thesis reports the preparation of Me-DLC based films by means of CAD techniques, as well as data concerning chemical, structural, morphological, tribological and mechanical properties. The process parameters were compared by studying the various mechanical properties of the films such as microhardness and residual stress. Incorporation of Cu-DLC multilayer reduced the stress value by about 4 GPa as determined by Raman spectroscopy. The friction tests revealed that the films possessed a superior friction performance with a friction coefficient of about 0.08. Specially, the (Cr:Cu)-DLC multilayer film exhibited a good wear resistance, though those Cu nanoparticle seemed to increase the friction coefficient. The XPS depth profiling measurement of the C element was kept approximately constant, whereas those of the Cr and Cu elements appeared to fluctuate periodically. A (Cr:Cu)-DLC coating membrane structure, which comprises hard and soft layers. An increase in the substrate bias voltage resulted in the varying of the sizes of Cu nanoparticles from 30 nm to about 3 nm.The overall quantity of the Cu nanoparticles decreased, while there was an increase in the substrate bias voltage, which mainly resulted from the kinetic energy of the ions to eliminate voids, asperities, and macroparticles efficiently. Substrate bias has a significant influence on the mechanical and tribological properties of the Me-DLC multilayers thin films deposited by cathodic arc deposition. The results with a lot of analyses show that the Me-DLC multilayers thin films prepared by CAD at the substrate bias of 120 V have high density and high sp3 fraction with low friction coefficient, high nanohardness and high elastic modulus values. The main advantages of this technology are to reduce intrinsic stress, increase deposition rate and make production more cost effective. This system may be extended to make other similar transition metal doped DLC films, which have great industrial application |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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