Effects of oxygen on the load-carrying action of some additives

Abstract The mechanisms of the load-carrying action of sulfur and phosphorus additives were investigated in air and argon, using the hot wire method and a four-ball machine. Results in the former experiment showed that the sulfurization reaction between sulfur compounds and an iron surface was considerably retarded in air, owing to the formation of iron oxide. It was confirmed that the higher the reactivity of the additive the better was its tribological behavior in the standard testing procedure, regardless of the atmosphere. Elementary sulfur was superior to dibenzyl disulfide or diphenyl disulfide. Oxygen was as important an EP agent as sulfur compounds under partial EHD lubrication. The results are discussed in relation to some transitions in wear and friction behavior.

[1]  S. Ikeda,et al.  The Mechanism of Reaction of Sulfur Compounds with Steel Surface During Boundary Lubrication, Using S35 as a Tracer , 1962 .

[2]  A. Rahmel.  Kinetic conditions for the simultaneous formation of oxide and sulphide in reactions of iron with gases containing sulphur and oxygen or their compounds , 1973 .

[3]  H. Okabe,et al.  Critical temperatures in ep lubrication , 1973 .

[4]  G. Salomon.  Failure criteria in thin film lubrication — the irg program☆ , 1976 .

[5]  F. Rounds.  Influence of Steel Composition on Additive Performance , 1972 .

[6]  Effect of Internal Stress on the Wear Behavior of Steel during Boundary Lubrication , 1974 .

[7]  Chemical Reactivity and Load Carrying Capacity of Lubricating Oils Containing Organic Phosphorus Compounds , 1970 .

[8]  T. Sakurai,et al.  Study of Corrosivity and Correlation between Chemical Reactivity and Load-Carrying Capacity of Oils Containing Extreme Pressure Agents , 1966 .

[9]  E. S. Forbes.  The load-carrying action of organo-sulphur compounds—A review☆ , 1970 .

[10]  H. Spikes,et al.  Additive Interference in Dibenzyl Disulfide Extreme Pressure Lubrication , 1974 .

[11]  A. D. Gee,et al.  Boundary lubrication of sliding concentrated steel contacts , 1972 .

[12]  A. Dorinson.  The Additive Action of Some Organic Chlorides and Sulfides in the Four-Ball Lubricant Test , 1973 .

[13]  H. Ravner,et al.  INHIBITION OF IRON-CATALYZED NEOPENTYL POLYOL ESTER THERMAL DEGRADATION THROUGH PASSIVATION OF THE ACTIVE METAL SURFACE BY TRICRESYL PHOSPHATE , 1970 .

[14]  D. Godfrey,et al.  Chemical Changes in Steel Surfaces During Extreme Pressure Lubrication , 1962 .

[15]  D. M. Sanborn,et al.  Temperature Measurements in Sliding Elastohydrodynamic Point Contacts , 1974 .

[16]  Donald H. Buckley,et al.  Oxygen and sulfur interactions with a clean iron surface and the effect of rubbing contact on these interactions , 1974 .

[17]  G. Vinogradov,et al.  Anti-wear and anti-friction properties of hydrocarbons under heavy loads , 1961 .

[18]  A technique for investigating reactions between E.P. additives and metal surfaces at high temperatures , 1960 .

[19]  H. Czichos.  Failure modes of sliding lubricated concentrated contacts , 1974 .

[20]  R. Fein,et al.  Chemistry of Boundary Lubrication of Steel by Hydrocarbons , 1965 .

[21]  M. Tomaru,et al.  Effects of some chemical factors on film failure under EP conditions , 1977 .

[22]  Heats of Adsorption and Anti-wear Properties of Some Surface Active Substances , 1975 .