TRIBOLOGICAL EVALUATION OF HYDROGEN-FREE ION-BEAM DEPOSITED DIAMOND-LIKE CARBON COATINGS

As part of a comprehensive program to study the films deposited by mas s selected ion beam deposition of carbon, initial results of an evalua tion of the tribological properties are reported. The dynamic friction coefficient, mu, in unlubricated conditions was measured and was foun d to decrease with increasing substrate temperature during IBD, above 150-degrees-C. This decrease complemented changes in other film proper ties, such as density, Raman spectrum and optical transmission which i ndicated a change from a diamondlike to a more graphitic nature with i ncreasing temperature. For films deposited at room temperature, the mi crohardness was found to be about 45 GPa with density very close to th at of diamond. A minimum value of dynamic friction was observed for io ns deposited at 120 eV. The results suggest use of the films for prote ctive coatings; friction coefficients of carbon coated magnetic record ing disks were measured.