Mechanical and tribological properties of PVD and PACVD wear resistant coatings

The article reports on the mechanical characterisation and tribological properties of hard carbon based coatings (a-C, Me-C:H, a-C:H) and MoS sub 2 coatings deposited on steel and polymer substrates. The films were deposited with PVD and PACVD deposition technique. DLC and Me-C:H coatings, such as WC-C:H or Cr-C:H, are promising for applications in fields where low friction coefficients are needed, e.g. in bearings. In uniball bearings good results were obtained with a Cr-C:H coating (2000 HV, thickness 10-15 mu m) to extend the re-lubrication intervals. In contrast to the ball joint greased steel/plastic couple in ball joints with enormous noticeable break-away at the starting motion the coatings on the plastic bowl achieve a clear reducing of these undesired stictions at the beginning of sliding movement.