No abstract

The tribological properties of two novel heterocyclic derivatives as additives in rape seed oil and in mineral oil were investigated using a four-ball machine. The morphologies and chemical features of the worn steel surfaces were observed and examined by means of X-ray photoelectron spectroscopy and scanning electron microscopy. Both heterocyclic compounds improved the load-carrying and extreme-pressure capacities and the friction-reducing and antiwear properties of rape seed oil more than they improved those of the mineral oil. Sudace analyses of the rubbed surfaces revealed the formation of a protective3lm containing FeSO,, organosulphur compound, FeS,, polymerised ester, and organonitrogen compound when the surfaces were lubricated by rape seed oil containing the additives. The protective film formed during sliding processes contributed to the increase in the wear resistance.