Tribological behavior of ZnO-Si₃N₄ nanoparticles-based lubricating grease

Abstract

Currently, nanoparticles have been widely used as lubricant additives, few researches have investigated their applications as additives for lubricating grease. In this paper, mixtures of ZnO and Si 3 N 4 nanoparticles were added into grease as additives. XRD and TEM were utilized to the investigate phase composition, microstructure and morphology of the nanomaterials. The composite grease was prepared by introducing ZnO and Si 3 N 4 nanoparticles into the grease matrix through ultrasonic dispersion. Then, tribological properties of the composite grease were measured through a MMW-1A universal friction tester. Results showed that the best lubrication performance was achieved when the composite grease contains 1 wt% ZnO and 0.5 wt%Si 3 N 4 . Under this condition, the friction coefficient and wear scar diameter decreased to 0.0701 and 0.727, which is 34.3% and 8.3% lower than that of the base greases, respectively. The morphology of composite nanoparticles is beneficial to the enhancement of antifriction property, which can be seen from SEM images. In addition, EDS analysis illuminated the accumulation of Zn and Si on the friction surface. Further researches proved its great potentials in alleviation of vibration, noise and temperature rise for high speed bearings, since the ZnO-Si 3 N 4 nanoparticles-based composite grease showed excellent lubrication and antifriction properties. ARTICLE HISTORY

A review on potentials and challenges of nanolubricants as promising lubricants for electric vehicles

“…44,51,57 For instance, He et al demonstrated that composite grease based on ZnO-Si 3 N 4 NPs has excellent potential for vibration reduction and temperature rise in high-speed bearings (55 000 rpm), coupled with excellent properties of lubrication and antifriction. 58 Another aspect of incorporating NPs as additives is their impact on grease's microstructure and rheological behaviour, but firstly, it is better to classify grease lubrication phases to comprehend the possible role of NPs. It is possible to classify the grease lubricating phases into two stages, based on the film thickness.…”

“…Only a few studies have been presented in investigating the use of nanocomposites in greases 44,51,57 . For instance, He et al demonstrated that composite grease based on ZnO‐Si 3 N 4 NPs has excellent potential for vibration reduction and temperature rise in high‐speed bearings (55 000 rpm), coupled with excellent properties of lubrication and antifriction 58 …”

Investigating Lubrication Mechanisms for Silicon Nitride Sliding on Steel: A Multifaceted Study

“…The lubrication regimes can vary from border lubrication, characterized by substantial direct contact with surface irregularities, to mixed and dynamic lubrication, where a lubricant coating is present to minimize wear and friction (Lee et al 2021). Examining the shift between these lubrication regimes offers an essential understanding of the circumstances in which Si 3 N 4 and steel can attain optimal effectiveness and lifespan (He et al 2018). The tribological efficacy of three commercially available EM lubricates was assessed using the wear and friction of Si 3 N 4 sliding over hardened steel.…”

Influence of various types of clays on velocity dependence of friction composites

“…21,22 Che et al 23 studied the effect of nano zirconium dioxide, silicon dioxide and aluminium oxide in friction materials for automotive brakes and concluded the wear resistance self-lubricating role of nanoparticles at the interface. He et al 24 studied the effect of zinc oxide and silicon nitride nanoparticles as a lubricant and investigated their role in reducing noise. The nanosized spherical molybdenum disulphide in the study of Dong et al 25 was ineffective in reducing the frictional noise and vibration in water-lubricated rubber materials.…”