Nano diamond oil additive is an effective anti-wear agent which increases the life span of an engine. It improves the lubrication of the friction pair and reduces wear. The nanodiamonds fill the micro scratches on the friction pair. They possess excellent lubrication properties and provide an alternative solution to replace the conventional graphite.
Nanodiamonds are highly crystalline particles with high hardness. They have chemical stability and nontoxicity. Additionally, they are stable enough to be dispersed in lubricants stably. Moreover, their surface has oxygen-containing reactive groups that facilitate the chemical reactions occurring on their surfaces.
Nanodiamonds can be dissolved in oil to produce a continuous film. Using this method, nanodiamonds have become a promising application area. In addition, nanodiamonds have also been applied in extreme pressure sliding lubrication.
A nanodiamond-containing composite additive has been reported to improve the smoothness of the friction pair and the oil film bearing capacity. It also decreased the friction coefficient by 20% to 30%. These effects are considered to be the result of the thin-film effect.
The thin-film effect is a mechanism by which the carbon and other elements in nanodiamonds penetrate the friction pair substrate. This lubrication effect is commonly found in ultra-precision manufacturing systems.
Various lubricating mechanisms have been proposed to explain the ball-bearing and thin-film lubrication effects. Nevertheless, the rolling and polishing effects of nanodiamonds are expected to play a critical role in the steel-copper interface. Moreover, the surface functionalization of nanodiamonds has been shown to improve load-carrying capacities.