Enhancing the tribological properties of biodegradable oils by organic additives under extreme conditions

• Main Authors: Akobuche W. Chikezie, Chinwuba Victor Ossia
• Format: Article
• Language: English
• Published: Malaysian Tribology Society 2018-12-01
• Series: Jurnal Tribologi
• Subjects: Enhancement; Characteristics; Biodegradable; Extreme condition; Additive
• Online Access: https://jurnaltribologi.mytribos.org/v19/JT-19-1-18.pdf

This study explores the enhancement of the lubricating characteristics of certain biodegradable oils such as palm-oil (Elaeis guineensis L.) and coconut oil (Cocos nucifera), relative to non-additive mineral lubricant under extreme conditions; the viscosity was measured according to ASTM D445 standards, test results proved mineral oil as having the highest viscosity, while the vegetable oils have the highest Viscosity Index. The wear and friction were measured using a pin-on-disc tribo-system according to ASTM G99-05 standards, while the four-ball machine was used according to ASTM D 2783 standards, to measure extreme pressure characteristics of the lubricants. After the enhancement of the bio-lubricants with a combination of red onions (Allium caepa L. var Tropeana) and Garlic extracts (Allium Sativum L.), the vegetable oils performed better than the mineral oil under extreme conditions, with coconut oil having the most superior extreme behaviors over other lubricants by sustaining the highest temperature of 240.500C and 160.30 seconds duration at 800Kgf. Minitab 16 was engaged to ascertain which of the predictors were more statistically significant on the responses; surface plots were used to evaluate relationships between the three variables at once and linear regression equations were used to correlate the input variables (load and speed) and the response (COF).