The Use of Unsaturated Hydrocarbons as Boundary Lubricants for Stainless Steels

Abstract

Friction and wear experiments with 1-cetene and cetane on stainless steel demonstrated the effect of a carbon-carbon double bond in the boundary lubrication of stainless steel. Experiments with cold-rolled steel, nickel, and chromium indicated the chromium to be the constituent in the steel that is markedly affected. The use of the unsaturated 1-cetene resulted in a lowering of the friction coefficient and the wear over its saturated analog, cetane. It is postulated that the improvement in friction and wear observed using the olefin 1-cetene is due to chemical attachment to the chromium or chromium oxide present in the wearing surface of the stainless steel reducing the amount of intermetallic contact. Experiments using the pure polar olefin vinyl stearate as the lubricant resulted in even further improvement of the frictional properties of stainless steel rubbing surfaces than the olefin alone, and a mechanism is proposed. It is also shown that these same improvements in frictional properties can be obtained when polar olefins such as vinyl stearate are used as additives to ordinary hydrocarbon oils.