Tribological surface chemistry of model lubricant additive measured in ultrahigh vacuum

WILFRED T. TYSOE; OCTAVIO JAVIER FURLONG; BRENDAN PAUL MILLER

Philadelphia, Pennsylvania

Conferencia; 244th ACS National Meeting; 2012

American Chemical Society

Lubricant additives react to form a lubricating film that can lower friction and/or prevent wear. At the high temperatures, the surface reaction and film growth kinetics are dominated by thermal processes. Under mild conditions, a surface film can be formed by shear-induced, surface-to-bulk transport. This is investigated by studying model sulfur- and boron- containing compounds on copper surfaces in UHV. The species that are formed by exposure of copper to the model lubricant additive is investigated using a range of surface analytical techniques to indentify the nature of the initial surface species. The effect of rubbing these adsorbate-covered surfaces is investigated, also in UHV, by measuring the friction coefficient and contact resistance during rubbing. The chemical composition of the wear track is followed using high-spatial-resolution Auger spectroscopy to follow the fate of the surface species caused by rubbing and to test the above postulate.