Microfriction and macrofriction of metal containing amorphous hydrocarbon hard coatings determined by AFM and pin-on-desk tests

Metal containing amorphous hydrocarbon films (Me-C:H) have excellent tribological properties and an adjustable electrical conductivity. Friction force microscopy investigations on gold- and tungsten-C:H films show a non-linear dependence of friction on the load in the nanonewton-range which can be explained by Hertz model of elastic contact. The effective friction coefficient and the interfacial shear stress strongly depend on the type of metal and the metal concentration inside the film. Microfriction and macrofriction (pin-on-disk) show a high qualitative correspondence.