Materials

Broken nanodiamonds create a super-long-lasting, very-low-friction dry lubricant

Computer simulation of the nanodiamond lubricant
Computer simulation of the nanodiamond lubricant
View 1 Image
Computer simulation of the nanodiamond lubricant
1/1
Computer simulation of the nanodiamond lubricant

"Broken nanodiamonds are forever," or so says a team of scientists at the US Department of Energy's (DOE) Argonne National Laboratory. By combining broken nanodiamonds with two-dimensional molybdenum disulfide layers, they've managed to produce a self-generating, very-low-friction dry lubricant with hundreds of applications that lasts practically forever.

Dry lubricants are an important tool for modern engineers, with a number of advantages over their liquid counterparts. Unlike greases and oils, dry lubricants aren't as chemically active, don't leak or squeeze out, and don't capture dust or grit. In addition, they don't break down at high temperatures and some work in the vacuum of space where liquids would evaporate or freeze solid.

One of the most common solid lubricants is graphite powder or paste, which is made up of plate-like carbon molecules with water molecules between them that act like extremely tiny ball bearings. It's used for lubricating locks, door knobs, and bicycle chains, as well as high temperature or high pressure environments. However, there are more exotic dry lubricants.

About three years ago, a team led by Anirudha Sumant of the Nanoscience and Technology division of Argonne found that by mixing graphene with nanodiamonds, it was possible for the first time on an engineering scale to produce superlubricity or near-zero friction. Now Sumant's team has taken this a step further by replacing the graphene with molybdenum disulfide – another common dry lubricant that's widely used in space industries because it performs well in a vacuum.

What they found was that when combined with molybdenum disulfide, the nanodiamonds spontaneously broke down and formed into balls of onion-like carbon. This was because the two-dimensional molybdenum disulfide molecules were disassociating into molybdenum and sulfur, which reacted with the nanodiamonds to form the layered balls by increasing the stress on their crystalline structure.

The result was a new dry lubricant that was 10 times slipperier than fluoropolymers like Teflon, that can sustain high contact pressure with very little wear, and tear and does not need to be applied in a thin film.

According to the team, the lubricant is also relatively inexpensive because, though molybdenum disulfide is more expensive than graphene, very little of it is needed for the proper effect to take place. Also, there are no hazardous chemicals involved and the lubricant is self-generating, so it effectively repairs itself during use.

The team sees the new, patented lubricant technology as having a wide range of applications, including bearings, pump seals, wind turbines, and magnetic disc drives.

"The material the lubricant is used on is going to last longer, and I don't have to worry about liquid residue and throwing out oily rags as part of the clean-up process," says John Harvey, business development executive at Argonne. "We also can use it to make parts that we can't make today, especially with metal stamping."

The research was published in Nature Communications.

The video below is a computer simulation of the nanodiamond lubricant.

Source: Argonne National Laboratory

Nanodiamonds are forever

6 comments
MakerDave
I used to use moly as a motor oil additive but read it could cause corrosion so I switched to tungsten. Does tungsten disulfide work with graphene in a similar way?
JimFox
What are "balls of onion-like carbon"? Do they have many concentric layers, do they make your eyes water??
guzmanchinky
10 time teflon? Wow, serious advance in lubrication. It would be so nice to never have to deal with oils and lubes again someday.
CAVUMark
Cheap too. So another great advancement, can we get it at Pep Boys?
zr2s10
I've got 5 immediate uses for this, and I'm sure I can come up with a few more! Of course, I could see this being very difficult to clean out of a system if it accidentally contaminates something. I hope to see more about it though.
KungfuSteve
This is really cool... however..... If this stuff "Lasts Forever".. how much environmental damage might it do, if massive amounts of this were dumped into the earth, waters... as well as to living things, from insects, to animals... especially us Peeps. Nana-Scale materials can potentially be as, if not far more, damaging to us, than Asbestos. Especially is the stuff can easily get carried into the wind, or absorbed into plants/food, ate / inhaled / absorbed into the body... where it might set off auto-immune responses, causing massive health crisis, and or it end up acting like a grinder/polisher ... tearing you up internally over a long period of time. (think ball-bearing loaded vibration polishers) If its even mildly unhealthy, then it should be limited at best... to very few critical areas (non-public) application... and with a proven system of cleanup/removal, in place. Asbestos was the bestos... until it was discovered that it caused lung cancer. Technology is great, but we have to realize the bigger picture. Everything in nature has a limited lifespan, for good reasons. There are those whom are trying to make mortals, immortal... extending lifespan dramatically.. or indefinitely. The problem with this... are numerous.. such as the fact, that over such a long span of time... DNA could get corrupted far too greatly... and thus reproduction lines, could get horribly mutated. Furthermore... the stagnant and slowed reproduction cycles... could make humans unable to keep up with changes from bacteria, and other environmental changes / evolution. People are blinded with desires and tend to think in such short-term ways... and the results are becoming catastrophic. We are in fact, being poisoned. Our DNA is being damaged beyond its abilities to self-repair. Each generation, is getting weaker and more and more corrupted... with health issues, mental and physical.. to mental capabilities. All the great Tech will be meaningless... if there are no healthy and sane humans left to enjoy it.