AVS 47th International Symposium
    Surface Engineering Monday Sessions
       Session SE-MoA

Paper SE-MoA8
Mechanical and Tribological Properties of Substoichiometric Oxide and Superstoichiometric Carbide Coatings for Wear Reducing and Lubricating Applications

Monday, October 2, 2000, 4:20 pm, Room 201

Session: Coatings for Extreme Environments: Wear Resistant, Lubricious, Anti-corrosive, High Temperature Coatings
Presenter: St. Bärwulf, University of Technology Aachen, Germany
Authors: St. Bärwulf, University of Technology Aachen, Germany
E. Lugscheider, University of Technology Aachen, Germany
K. Bobzin, University of Technology Aachen, Germany
Correspondent: Click to Email
The tungsten and vanadium oxides are promising to be usable as solid lubricants at elevated temperatures because of their ability to form non stoichiometric Magnéli-phases with reduced shear strength. So far they were mainly investigated as powdery material or as a component of ceramics for tribological or machining applications. As a matter of fact metal-oxides are interesting for tribological insets at atmospheric conditions because of their expected oxidation stability, hardness and low adhesion against the counterbody. For low temperature insets carbon containing coatings are meanwhile widely spread in numerous applications. Because of their phase generation / transition the zircon- and hafnium-carbon systems offer a very interesting possibility to deposit graded coatings with self-adapting properties in dependance on the external mechanical load and the contact conditions. This self-adapting effect will be shown exemplarily for a hydraulic component after an inset under load in relative motion. The presentation will report about the mechanical and tribological properties of these coatings. Further possible ranges of applications will be deduced from the fundamental characterization and results of concrete insets (e.g. machining) shown. Therefore the coatings were analyzed by various testing methods to characterize the tribological, mechanical and structural properties, like contact angle measurements, SEM, scratch testing, nanoindentation, XRD and pin on disk.