Effects of Mango Seed and Castor Seed Oils with Nanoparticle Additives on Friction and Wear Performance of Steel-Steel Contacts

Investigation of the effects of mango (mangifera indica) seed oil and castor (ricinus communis) seed oil-based lubricants on friction and wear performance of steel-steel surface contacts was carried out in this study. Petroleum-based lubricants are hazardous and contaminate the environment. There is need to develop credible alternatives, which are biodegradable and environmentally friendly. The Soxhlet extraction method was used to extract vegetable oils from these seeds. The oils were subjected to laboratory analyses and formulations with nanoparticles additives. Friction and wear performance tests were carried out on the pin-on-disc apparatus according to ASTM G 99 standard. The addition of nanoparticles to pure mango seed oil and castor seed oil, respectively, improved their coefficient of friction by 21%, and 41%, respectively, and performed well in comparison to SAE20W50. Wear test results showed that pure mango seed oil and pure castor seed oil, and 1% titanium dioxide nanoparticle in mango seed oil have, respectively, 23%,7% and 36% better total wear performance than the reference commercial engine oil (SAE20W50). Among samples of castor oil formulated with nanoparticles, 2% aluminum oxide had the best wear performance, but the resulted wear mass loss was 20% higher than the result obtained from the SAE20W50l. Wear scars on the steel surfaces were analyzed with scanning electron microscope. The performance of these vegetable oils confirmed that they are excellent candidate lubricant oil-based stock that should be fully exploited and utilized.