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The adsorption and reaction of water and ethanol with polycrystalline TiC coatings have been investigated and compared with those of the nonpolar (100) face of single crystal TiC. This work is pursued to develop a fundamental understanding of the surface bonding and reaction properties, thus enabling the use of TiC as a tribological coating material. Temperature-programmed desorption has been used to characterize the desorption behavior of these model adsorbates as well as that of products resulting from their reaction with the TiC surface. Following adsorption at 100K, molecular desorption as well as desorption of reaction products is evident for both water and ethanol. Approximately 70% of the water in the monolayer is judged to irreversibly react with the TiC surface, producing a surface oxide and gaseous hydrogen and carbon monoxide. Approximately 92% of the ethanol in an adsorbed monolayer reacts, predominantly producing gaseous ethene. These results are similar to those on TiC(100) surfaces, althoug...

Co-sputtered thin films have been deposited from MoS2 and WSe2 targets in order to investigate the relationships between tribological behavior and film microstructure. The stoichiometries of pure films for the sputtering conditions used, were found to be MoS1.6 and WSe1.5 as measured by wavelength dispersive x-ray analysis. The mechanical properties of the composite films were investigated by pin-on-disk wear testing in 50% relative humidity air as a function of WSe2 concentration. X-ray diffraction measurements indicate that the microstructure is strongly affected by the inclusion of WSe2 and there is a strong correlation between microstructure and tribological performance. X-ray and Raman measurements indicate a large increase in the c axis of the MoS2, which may be due to intercalation. X-ray photoelectron spectroscopy measurements show no evidence that either Se or W chemically substitutes into the MoS2 structure.

Co-sputtered thin films of MoSx with Au have been deposited in order to investigate the relationships between tribological behavior and film microstructure. The mechanical properties of the composite films were investigated by pin-on-disk wear testing in 50% relative humidity air as a function of Au concentration. X-ray diffraction measurements indicate that the microstructure is strongly affected by the inclusion of Au and that there is a strong correlation between microstructure and tribological performance.