A STUDY OF N, O AND S HETEROCYCLIC-COMPOUNDS AS EXTREME PRESSURE LUBRICANT ADDITIVES

The potential EP activity of certain synthetized 2-arylamino-5-(4′-pyridyl)-1,3,4-oxadiazoles and 2-arylamino-5-(4′-pyridyl)-1,3,4-thiadiazoles has been evaluated using a four-ball lubricant testing machine. All of the additives were found to be effective at higher loads; however, 2-p-methoxyphenylamino-5-(4′-pyridyl)-1,3,4-oxadiazole and 2-p-chlorophenyl-amino-5-(4′-pyridyl)-1,3,4-oxadiazole have shown good activity. The surface topography of the bearing ball wear scars was studies using scanning electron microscopy and electron probe micro-analysis techniques. © 1990.