Tribological effects of Cu, Fe and Zn nano-particles, suspended in mineral and bio-based oils

Abstract

Many studies focus on nanoparticles as lubricity additives but overlook the fact that wear produces nanosized debris during the field use. In order to simulate the fine metal contaminants, which are the most widespread in various field applications, prefabricated Fe, Cu and Zn nanoparticles were used. Their 0.01–1% suspensions in vegetable and mineral oils with or without ZDDP and ashless AW package were tested on four‐ball AW under 150‐N load. Tribological effects of nanoparticles were not significant in formulations without AW additives. However, nanoFe addition produced notable lubricity improvement in already excellently performing rapeseed formulation with ZDDP, while such addition reduced performance of the ashless AW pack. Results show that metal nanoparticles can play both positive and negative roles on additive effectiveness and nanosized contaminants can significantly affect the lubricant performance. Copyright © 2015 John Wiley & Sons, Ltd.

Tribological Behaviour of Neem Oil with and without Graphene Nanoplatelets Using Four-Ball Tester

“…As GNPs loading increases, nanofillers agglomerate and create bigger and asymmetric particles, which prevent movement of fluid layers on each other; hence the viscosity increased for higher loadings (0.75 and 1.0 wt.%) of GNPs-NO nano-lubricants. e same behaviour was observed by other researchers with different liquids and nano additives [54][55][56][57]. Wang et al observed about 86% improvement in the viscosity of distilled water on incorporation of Al 2 O 3 [54].…”

Effects of Electrolyte and Ti Layers on Static and Dynamic Friction of Anodized Alumina

“…Static COF was measured using 100 Hz data collection rate for improved sensitivity. COF data at such high collection rate is strongly affected by surface roughness and debris particles [10,11]. Therefore, fluctuations of COF curve were smoothened by averaging every 15 data points to get a representative segment of initial 10 friction cycles, Fig.…”

Suitable additives for vegetable oil‐based automotive shock absorber fluids: an overview

“…This would suggest engaging iron particles in formulating VOs as magnetorheological fluids for ASA; nonetheless, the oxidation catalytic effect of this particles can be a barrier, unless a powerful chelated metal deactivator is employed. At the moment, it is uncertain whether metallic particles significantly improve lubricity of VOs, because the tribological behaviour of fine Cu, Fe and Zn nano‐particles at 0.1–1% wt in inhibited rapeseed oil were reported by Asadauskas and co‐researchers to not only have effects on the performance of the lubricant, but can also have ambivalent impacts on additives effectiveness. All the same, there are surface protection powder additives in nanoscale, which are effective in VOs.…”