Abstract
In order to study phase-by-phase sliding behavior of complex alloys in electrochemical environments, a scanning probe technique has been developed in the AFM to conduct nanoscale wear tests in an electrochemical cell. By controlling the kinematics, contact pressure, and electrochemical conditions, the electrochemical response to sliding by the tip may be linked to individual microstructural features. Moreover, analysis of the local wear rates may be performed. However, little is known about the effect of tip material on the tribochemical behavior during these scanning probe experiments. In the present study, duplex stainless steel was heat treated to induce secondary phase transformations, sensitizing the alloy to tribocorrosion. Two different tip materials were used: monolithic diamond glued to a cantilever using a dielectric glue, and diamond coated silicon tips. Vastly different electrochemical responses to sliding were obtained using these materials. The mechanisms therein, their implication for wear in electrochemical environments, and their connections to more common tribocorrosion experiments will be described.
*NRC Postdoctoral Research Associate cited in Chemistry Division, NRL
1 Molecular Interfaces and Tribology Section (Code 6176), NRL
2 Center for Corrosion Science and Technology (Code 6134), NRL