INTERACTION OF SOME EXTREME-PRESSURE TYPE LUBRI¬CATING COMPOUNDS WITH AN IRON SURFACE

摘要

An iron surface was exposed to the extreme-pressure type lubricant additives benzyl chloride, dichlorophenyl phosphine, dichlorophenyl phosphine sulfide, and dichlorophenyl phosphine oxide. Iron, in the sputter-cleaned state, was exposed to these materials statically and during dynamic friction experiments. With benzyl chloride only chlorine adsorbed to the surface, and with di¬chlorophenyl phosphine no adsorption occurred, while the addition of sulfur to that same molecular structure resulted in the promotion of carbon and chlorine adsorption. Substitution of oxygen for sulfur in the dichlorobenzyl phosphine molecule resulted in carbon, chlorine, and oxygen adsorp¬tion. With none of the phosphorus containing molecules was phosphorus detected on the surface. Sliding in an atmosphere of benzyl chloride promoted adsorption of chlorine to the iron surface. Increases in load resulted in a decrease in the surface concentration of iron chloride.