In-situ studies of the competitive adsorption of lubricant additives

It is known that different types of surface-affine
additives (i.e. antiwear/anti-corrosion/ anti-friction) can
have very different adsorption behaviour on surfaces
(e.g. [1–3]). The interactions can be synergistic or
antagonistic in character and influences the near-surface
chemistry of the sliding surfaces and therefore also the
tribological performance of the system. For wear
protection additives, it is for instance known that
phosphor and sulfur containing layers are formed under
tribological conditions (e.g. [4,5]). In this presentation
we will give an overview on an ongoing study of the
adsorption of selected additives using novel in-situ
approaches. The found correlations are also compared to
tribological experiments in order to answer the question
whether synergistic effects in adsorption also lead to
synergistic effects in wear reduction.