Improvement of Lubricants Tribological Properties Using Some Oxygen Organic Compounds

Abstract

In the current work, a number of standard tests, for several additive compounds used to improve the capability of the lubricants to reduce the friction and hence the wear, have been performed to determine the activity of these compounds. The tests, which include diameter of the wear trace, friction coefficient and the thickness of the insulating layer, have been carried out under the tribological conditions, that is, under the boundary friction conditions. Tribological analyses for the compounds were established by using the (HFRR) instrument. The pin-on-disc technique was employed. The results showed that a maximum wear active was found with hexadecane; however, all the additives were active in decreasing the wear of the metallic ball. In addition, the activities were enhanced by ascending their concentrations in hexadecane. Moreover, the most active compounds at 100ppm and 300 ppm were 16-hydroxyhexadecanoic acid and C₃₆ dimer acid/ 1,6-hexanediol mono ester, respectively. Furthermore, the least friction coefficient at 100 ppm and 300ppm was found to be 0.115 for 16-hydroxyhexadecanoic acid and 0.066 for C₃₆ dimer acid/1,6-hexanediol monoester, respectively. Finally, the highest thickness of the insulating layer between the fractioned surfaces at 100 ppm and 300 ppm was found to be 48% for 16-hydroxyhexadecanoic acid and 81.3% for C₃₆ dimer acid/1,6-hexanediol monoester, respectively