Effect of the Prepared Proceeding on Mechanical and Tribological Properties of DLC Films

Abstract

In order to analyze the effect of proceeding on the mechanical and tribological properties of DLC films. Three DLC films samples on single silicon wafers were prepared by CVD method. The changed bias voltages were 300V, 350V, 450V separately. The structure and topography of prepared films were studied by Raman spectroscopy and atomic force microscopy (AFM), respectively. The hardness and elastic modulus together with friction coefficient of DLC films were measured by Tribolab system. According to the Raman spectra, the G and D peak shift to left with the increasing of bias voltage. Nano indent showed that the hardness (H) of the DLC films decreases from 19.63GPa to 18.12GPa with the increasing of bias voltages, and the value of elastic modulus (E) is also behaving the same trend as H from 157.95GPa to 146.95GPa. Friction coefficients of the three samples were measured by nano-scratch method under the constant normal load of 1000uN and the slide velocity of 3 um/sec, the corresponding friction coefficient is 0.0804 for DLC300, 0.0508for DLC350 and 0.0594 for DLC450 separately, which indicates that high hardness materials may not necessarily the perfect frictional material, but compound properties of hardness and elastic modulus