Effect of the size and morphology of particles dispersed in nano-oil on friction performance between rotating discs

Abstract

Various carbon-based particles such as graphite, carbon black, graphite nanofibers and carbon nanotubes were dispersed in mineral oil to systematically examine the effect of the size and shape of particles on the properties of friction performance. As the results of friction tests using a disc-on-disc tribotester, the friction coefficient of a disc specimen was significantly reduced when nano-sized spherical particles were suspended in mineral oil. This was attributed to the presence of spherical nanoparticles, which prevented direct contact between frictional surfaces. However, the fibrous nanoparticles with high aspect ratios deteriorated the lubrication performance between friction surfaces due to a higher degree of agglomeration.

Rheological behavior of multiwalled carbon nanotube-imidazolium tosylate ionic liquid dispersions

“…In the recent years, the combination of ILs and oils with several types of nanophases has given rise to new nanostructured dispersions, with promising engineering applications [7]. Among available nanomaterials, carbon nanostructures such as nanotubes showed promising results as additives in lubricant oils, due to the weak van de Waals forces between the sliding surfaces [8]. In particular, multi-walled carbon nanotubes (MWCNTs) have been widely used in solid lubrication [9,10] and as lubricant additives [11,12].…”

Copper oxide nano-particles as friction-reduction and anti-wear additives in lubricating oil

“…Vadiraj et al investigated the effect of nano boric acid and nano copper based engine and transmission oil additives in different volume ratios (1:10, 2:10, and 3:10) on friction and wear performance of cast iron and case carburized gear steel [5]. Hwang et al studied the effect of the size and morphology of nanoparticles suspended in lubricating oils on the lubrication performance [6]. It has been reported that the main mechanism behind friction reduction due to nanoparticles can be attributed to rolling/sliding effect, protective film, third-body, and mending effects [7].…”

Nanodiamond: A high impact nanomaterial

“…This well-defined shape and size makes them ideal for applications where a high specific surface area ($300 to 400 m 2 /g) is required, for instance in the uploading of drugs [23,46] and bioligands, or the formation of a dense network of bonds between ND nanofillers and a surrounding polymer matrix [47,48]. Rounded particles are inherently more effective in lubrication and polishing applications [49]. Coupled with the high mechanical strength of the diamond core which can withstand high localized stress, the rounded shape ensures minimal contact area with sliding surfaces, and NDs can act as nanoscale ball bearings.…”