| AVS 64th International Symposium & Exhibition | |
| Tribology Focus Topic | Wednesday Sessions |
| Session TR+AS+HI+NS+SS-WeA |
| Session: | Molecular Origins of Friction |
| Presenter: | John Curry, Lehigh University |
| Authors: | J.F. Curry, Lehigh University M. Wilson, Sandia National Laboratories T.F. Babuska, Sandia National Laboratories M. Chandross, Sandia National Laboratories H. Luftman, Lehigh University N.C. Strandwitz, Lehigh University B.A. Krick, Lehigh University N. Argibay, Sandia National Laboratories |
| Correspondent: | Click to Email |
Molybdenum Disulfide (MoS2) is a solid lubricant used widely in aerospace applications, capable of providing ultralow friction (coefficients, µ < 0.01) in inert environments such as the vacuum found in outer space. Research over the years has led to the development of MoS2 nanocomposites that are less susceptible to the effects of environment and aging. Yet, the fundamental mechanisms responsible for environmental sensitivity and degraded friction behavior remain highly debated. Tribological experiments and molecular dynamics (MD) simulations were used to understand the evolution of friction behavior for MoS2 coatings as a function of temperature, lattice commensurability and defect density. The oxidative resistance of MoS2 coatings prepared with differing degrees of defect density and basal orientation was also assessed via high-sensitivity low-energy ion scattering (HS-LEIS) depth profiling, X-ray photoelectron spectroscopy (XPS), tribological experiments and MD. Through these findings, we discuss new connections between atomic-scale mechanisms and macro-scale friction behavior of this class of lubricant in a wide range of environments.