Accession Number : ADA555124


Title :   Temperature and Water Vapor Pressure Effects on the Friction Coefficient of Hydrogenated Diamondlike Carbon Films


Descriptive Note : Journal article


Corporate Author : ARGONNE NATIONAL LAB IL ENERGY TECHNOLOGY DIV


Personal Author(s) : Dickrell, Pamela L ; Argibay, N ; Eryilmaz, Osman L ; Erdemir, Ali ; Sawyer, W G


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a555124.pdf


Report Date : Jul 2009


Pagination or Media Count : 6


Abstract : Microtribological measurements of a hydrogenated diamondlike carbon film in controlled gaseous environments show that water vapor plays a significant role in the friction coefficient. These experiments reveal an initial high friction transient behavior that does not reoccur even after extended periods of exposure to low partial pressures of H2O and O2. Experiments varying both water vapor pressure and sample temperature show trends of a decreasing friction coefficient as a function of both the decreasing water vapor pressure and the increasing substrate temperature. Theses trends are examined with regard to first order gas-surface interactions. Model fits give activation energies on the order of 40 kJ/mol, which is consistent with water vapor desorption.


Descriptors :   *GAS SURFACE INTERACTIONS , ADSORPTION , DIAMOND FILMS , EXPERIMENTAL DESIGN , HYDROGENATION , REPRINTS , SOLID LUBRICANTS , SURFACE PROPERTIES , TEMPERATURE , TRIBOLOGY , WATER VAPOR


Subject Categories : Coatings, Colorants and Finishes
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE