Nanomechanical and nanowear properties of Cr3C2 thin films deposited by rf sputtering

In this investigation, nanoindentation, nanoscratch and nanowear tests were done in order to study the nanomechanical and nanotribological properties of the chromium carbide nanostructured thin films. Chromium carbide films were synthesized by rf sputtering from a Cr3C2 target on magnesium oxide substrate. The samples were characterized by X-ray diffraction and grazing X-ray reflectivity. All the films have a thickness of 300nm. A pyramidal Berkovich indenter diamond tip was used for nanomechanical testing. The residual wear depth of the samples was examined using an atomic force microscope (AFM). In this study, an experimental method adapted to the nanowear properties was explored. We have studied the influence of the substrate temperature on the structural, mechanical and tribological properties of chromium carbide films. We have shown that Cr3C2 films deposited at a substrate temperature up to 600°C exhibit a better wear resistance and a hardness value higher than what is measured in the case of the films deposited at room temperature.