AVS 57th International Symposium & Exhibition
    Tribology Focus Topic Wednesday Sessions
       Session TR+MN+NS+SS-WeM

Paper TR+MN+NS+SS-WeM12
First Principles Calculations and Atomistic Simulations of Tribology at Sliding Molybdenum Disulfide Surfaces

Wednesday, October 20, 2010, 11:40 am, Room Tesuque

Session: Influence of Atmosphere, Temperature, and Materials on Friction
Presenter: S.B. Sinnott, University of Florida
Authors: T. Liang, University of Florida
S.R. Phillpot, University of Florida
S.B. Sinnott, University of Florida
Correspondent: Click to Email
Molybdenum disulphide is the most commonly used solid lubricant coating in aerospace applications. In this work, we carry out first principles density functional theory (DFT) calculations of the potential energy surface between two MoS2 surfaces and examine the influence of oxidation on the results. In addition, we present the results of a recently developed empirical many-body potential for Mo and S systems and examine nano-scale friction between sliding MoS2 surfaces using classical molecular dynamics (MD) simulations. In particular, MD simulations of interfacial sliding at various loads, temperatures and sliding directions are carried out. The loads and friction forces are extracted to calculate the friction coefficient of the MoS2 as a function of temperature, and the results are compared to experimental pin-on-disk measurements of MoS2 coatings and atomic force microscopy measurements on single crystal MoS2 surfaces. The results from both the DFT calculations and the MD simulations help us to better understand the origins of lubricity on MoS2.