Exploration of PTFE sub-micron particles for enhancing the performance of commercial oils

Abstract

This paper reports on the tribo-performance enhancement of commercial gear oil and engine oil by inclusion of PTFE particles of submicron (230 nm) size (SMPs). It also reports on the investigations on various concentrations of SMPs to find the optimum doses. Results revealed that optimum dosage of 6 and 3 wt.% SMPs led to a significant improvement in EP property by 175% and 58% respectively in Engine oil and Gear oil. The EP performance of PTFE added engine oil surpassed that of PTFE added-gear oil confirming that it can be used as multipurpose oil. Importantly anti-wear and anti-friction properties also showed improvement confirming no antagonistic influence of PTFE particles on selected commercial oils. Synergistic action between SMPs and other additives led to formation of stable tribo-film as a result of chemical interaction of mating surfaces. The mechanisms involved were analyzed by investigating worn surfaces using SEM-EDX, x ray photoelectron spectroscopy (XPS) techniques. The stability of suspension in case of engine oils was up to 2 months and for gear oil it did not show any deterioration in the observed period of 4 months.

A Methodological Approach to Assessing the Tribological Properties of Lubricants Using a Four-Ball Tribometer

“…The specific wear work serves as an integral energy parameter whose value can be used to evaluate the anti-wear and extreme pressure properties of lubricants. This manuscript is a continuation of the work presented in [26] and offers an improved technique for the assessment of tribological properties. This work takes into account the requirements outlined in the ASTM D4172 and ASTM D2783 standards.…”

“…The works in [25,26] consisted of experimental studies on the tribological characteristics of lubricants using a four-ball tribometer with polytetrafluoroethylene additives. Appropriate concentrations of polytetrafluoroethylene additives in base oils were established.…”

“…All the works mentioned relied on tests conducted using a four-ball tribometer [14][15][16][17][18][19][20][21][22][23][24][25][26]. In [27,28], the authors proposed an energy parameter, namely the specific work of the wear of a test material composed of ball-bearing steel in the tested lubricating medium, to assess the tribological characteristics of lubricants.…”

“…According to the authors of the referenced works [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28], testing on a four-ball tribometer provides highly reproducible results across multiple experiments and offers valuable data. In our view, conducting tests on a four-ball tribometer should be the primary and essential step in the study of lubricants, both liquid and plastic.…”

“…The developed technique and the integral parameter for the estimation of the tribo- Further development of this method for the testing of lubricants on a four-ball tribometer aims to enhance the efficiency of screening tests during the development of new lubricants, such as vegetable oils. Lubricant additives using nanomaterials, such as fullerenes, are actively being developed, as discussed in [26]. Additionally, this parameter can be utilized in modeling friction and wear processes in tribo-systems to monitor the lubricating medium, as presented in [24,27].…”