Several my papers have been devoted to using nanosized copper, brass and zinc particles as additives to lubricants. Also I reviwed a lot of papers relating to this subject.

Thanks for replies. I have reference and scientist level interaction on lab scale trials. I am looking for articles explaining actual industrial trials of nano lubricants to understand its operational performance like bearing temperature reduction, auxiliary power consumption reduction etc  Any such reports please?

I have some reports in Russian on industrial scale tests of nanopower additives to motor oil for diesel quarry  trucks. The results show reduced by 28% smokiness and 18 to 25% wear reduction on adding the nanolubricant to motor oil.

 Dear Sergie, thanks for the information. 

Dear Sergie,  Which nanoadditive (material) was used to get above results?

That was copper nanopowder. However, even  better results have been achieved using brass nanopowders but I have no figures on them.

Thanks..While using copper /brass nano particles any erosion problem reported on engine parts? There were reports of erosion when micron sized particles used to enhance heat transfer in fluids.

There always a big problem of nanopowder aggomeration, settling down, clogging filters and so on . But I have never met erosion inflicted by ductile metal nanopowders. Moreover, nanoparticles may form  a kind of composite antiwear film.

Hexagonal boron nitride nano powder is also used as lubricant. I am sharing the website of the turkish company BORTEK that I once upon a time did an internship.  They have products in the industrial level. You might want to check : 

http://www.borteknolojileri.com/en/index.php

As far as I know a lot of different materials have been tested as lubricant additives, including mineral powders such as, for example, serpentine . hBN has long been used as a component of greases along with molybdenum disulfide and graphite/

we have so many kind of nano lubricants,select of them is related to your materials and so on.for example so  many literature suggest PTFE and MoS2 and Graphite and PFPE.

It is true that friction and operating temperature decreases on the use of nanolubricants.  We carried out experiments with hBN, graphene, MoS2, PTFE, Nanodiamond etc in various oils (fully formulated oils) and found that in all the cases there is a decrease in friction and Operating Temperature.  We observed larger decrease in the experiments with nanodiamond .   Presently, nanodiamond,  products are available in Indian Market claiming energy efficiency up to 30%  in different oils.

Dr Sastry, Thanks. Any IOCL lubricant product based on nano diamond available in market?

If you are considering nanodiamond-containing lubricants, you should learn about the advantages of in situ nanopolishing (ISN) lubricant technology.  Nanodiamond agglomerates and tends to impregnate the metallic surfaces under force, whereas ISN technology produces (harder-than-diamond) spheres that permanently remove the rough asperities from the metal surface.  ISN is a permanent solution to friction elimination.

We have successfully developed graphene based nanolubricant and trialed in large scale industrial machines. 5 % energy savings noticed during performance evaluation without  any operational or maintenance issues.

What you are describing is the (ex situ) addition of exfoliated graphene nanoplateletes to conventional lubricant. ISN synthesizes graphene (in situ) as a tribofilm over the moving parts from within the system (engine, turbine, bearing, gears, etc.).  With small (externally added) graphene nanosheets, you can never guarantee that the sheets will arrive at the correct location (set of asperities) at the exact time necessary to reduce the frictional contact and further, GNPs do nothing to remove the source of the friction problem - the asperities themselves (no polishing effect).  This is why ISN is able to produce the remarkable results in efficiency (recently, 25% increase in lorry fuel economy within 1,500 km of use) unheard of with any other lubrication technology.

At the Emission Control conference in Dresden, we will present a paper about an extensive RDE trial with very positive results from a nanoparticle product which acts at 20ppm in the engine oil.

(this work is not through my TU Deft affiliation but my private business)

We have developed process to prepare exfoliated graphene in lubricating oil and developed a product for industrial gear oil and evaluated its tribological performance. It gave ~40% reduction in temperature of the oil and reduction in friction coefficient. However, we are facing partial sedimentation of graphene after a few weeks. Do you have any experience in reducing the sedimentation on long time storage?