A new range of nano lubricants developed by the U.S. Department of Energy's Argonne National Laboratory incorporates an exceptionally low coefficient of friction.
The new lubricant uses nano-scaled particles of boric acid 50nm in diameter, offering excellent lubricity and stability as well as reduced energy losses due to friction and heat generation.
A boric acid compound, which is also used as a mild antiseptic and eye cleanser, the lubricant is derived from the readily available boron and is formed of crystalline layers. Each such layer has a very tight internal bonding but weak bonding between the layers. These layers stack themselves relatively far apart, so that the intermolecular bonds, known as van der Waals forces, are comparatively weak.
When stressed, the compound's layers easily smear and slide over one another, likened to a strewn pack of playing cards. The strong bonding within each layer prevents direct contact between sliding parts, lowering friction and minimising wear.
Metals covered with a boric acid film exhibited coefficients of friction lower than that of PTFE, making these films amongst the slipperiest solids in existence.
This nano lubricant may offer another benefit in diesel engines by replacing sulphur, which is used to improve lubricity in diesel fuel but causes harmful acidic emissions.
Another development in the US involves synthetic diamond particles of nano size that have been effectively incorporated into lubricants. This nano lubricant of 5nm particle size and under has a nano ball-bearing-like structure, which enables it to reduce friction very efficiently even with rough contacting surfaces.
Trillions of nano particles act like ball bearings in the grease or oil. These nano lubricants are effective even on non-polished surfaces and have the additional effect of micro-polishing the surfaces whilst in service so that the friction is further reduced.
Key features of synthetic diamond lubricants:
- Used as a space lubricant as it doesn’t freeze or melt in the extreme cold and heat of outer space
- Can withstand temperature extremes beyond the capabilities of some of the best synthetic oil carriers
- Smaller particles will permanently embed themselves into the friction surfaces and larger particles will roll between, keeping the diamond hardened friction surfaces from touching
GreaseMax lubricators are available in Australia through Delta Distribution .