BOUNDARY LAYER LUBRICATION . MONOLAYER OR MULTILAYER

A critical review of some literature on the properties of liquids squeezed between two solid flats is presented. The experimental data are discussed and examined in detail. Although some of the experimental results may be questionable, most of the data appear to be qualitatively valid and cannot all be attributed to dirt or impurities in the liquids or asperities on the flats. The simplest and most satisfactory way of accounting for the observed results is to postulate the existence of a film, the properties of which are far different from those of the bulk liquid. It is found that the best model for such films is an ordered-liquid model in which the wall forces, though not strong enough to bind more than a few layers, induce long-range order in the fluid. © 1969.