Abstract
Synthetic diamond films have attracted great attention for their extreme properties and potential engineering applications as protective and wear-resistant coating for cutting tools. Nanocrystalline diamond (NCD) coatings were synthesized from CH4/H2/Ar (1/10/89%) microwave plasma at four deposition temperatures (TD) ranging from 653 to 884 °C. The hardness (H) and Young's modulus (E) of NCD coatings measured at three different loads (10, 25 and 47 mN) depended on the nanoindentation load-level. The NCD coating produced at the lowest TD showed values of H = 121 ± 25 GPa and E = 1036 ± 163 GPa at the highest load. This result was attributed to the formation of elongated nanocrystallites at low deposition temperature. Further, the NCD coating obtained at lower deposition temperature exhibited an anomalous indentation size effect (ISE), i.e. a reverse ISE (RISE), which was ascribed to the heterogeneity of grain sizes along the [220] and [111] directions. Finally, a positive and negative (inverse) Hall-Petch behavior was observed for grain sizes along the [111] and [220] directions, respectively.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
