  An overview of computer simulations of tribology is presented. The chapter
begins with a brief overview of simulation techniques and the special
requirements for simulations of tribological processes. Then simple
one-dimensional models of friction between crystalline surfaces are introduced
to illustrate general features of friction, such as the importance of
metastability and the effect of commensurability. Next two- and
three-dimensional studies of dry sliding between crystalline surfaces are
described, and compared to scanning probe experiments and measurements of the
friction on adsorbed monolayers. Lubrication is then discussed, starting from
thick films and describing the breakdown in bulk hydrodynamics as the thickness
of the lubricant decreases to molecular scales. Deviations from the usual
no-slip boundary condition are quantified and the onset of solid behavior in
molecularly thick films is described. The possibility that solidification of
thin layers of adventitious carbon is responsible for the prevalence of static
friction is explored. The final sections describe stick-slip motion,
tribochemical reactions, machining, and the evolution of microstructure in
sliding contacts.
